Word wrap
You are encouraged to solve this task according to the task description, using any language you may know.
Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way in your language. If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
Show your routine working on a sample of text at two different wrap columns.
Extra credit! Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm. If your language provides this, you get easy extra credit, but you must reference documentation indicating that the algorithm is something better than a simple minimimum length algorithm.
If you have both basic and extra credit solutions, show an example where the two algorithms give different results.
Ada
The specification of a class Word_Wrap.Basic in a package Word_Wrap: <lang Ada>generic
with procedure Put_Line(Line: String);
package Word_Wrap is
type Basic(Length_Of_Output_Line: Positive) is tagged private;
procedure Push_Word(State: in out Basic; Word: String); procedure New_Paragraph(State: in out Basic); procedure Finish(State: in out Basic);
private
type Basic(Length_Of_Output_Line: Positive) is tagged record
Line: String(1 .. Length_Of_Output_Line);
Size: Natural := 0; -- Line(1 .. Size) is relevant
Top_Of_Paragraph: Boolean := True;
end record;
end Word_Wrap;</lang>
The implementation of that package:
<lang Ada>package body Word_Wrap is
procedure Push_Word(State: in out Basic; Word: String) is
begin
if Word'Length + State.Size >= State.Length_Of_Output_Line then
Put_Line(State.Line(1 .. State.Size));
State.Line(1 .. Word'Length) := Word; -- may raise CE if Word too long
State.Size := Word'Length;
elsif State.Size > 0 then
State.Line(State.Size+1 .. State.Size+1+Word'Length) := ' ' & Word;
State.Size := State.Size + 1 + Word'Length;
else
State.Line(1 .. Word'Length) := Word;
State.Size := Word'Length;
end if;
State.Top_Of_Paragraph := False;
end Push_Word;
procedure New_Paragraph(State: in out Basic) is
begin
Finish(State);
if not State.Top_Of_Paragraph then
Put_Line("");
State.Top_Of_Paragraph := True;
end if;
end New_Paragraph;
procedure Finish(State: in out Basic) is
begin
if State.Size > 0 then
Put_Line(State.Line(1 .. State.Size));
State.Size := 0;
end if;
end Finish;
end Word_Wrap;</lang>
Finally, the main program:
<lang Ada>with Ada.Text_IO, Word_Wrap, Ada.Strings.Unbounded, Ada.Command_Line;
procedure Wrap is
use Ada.Strings.Unbounded;
Line: Unbounded_String; Word: Unbounded_String;
function "+"(S: String) return Unbounded_String renames To_Unbounded_String; function "-"(U: Unbounded_String) return String renames To_String;
package IO renames Ada.Text_IO;
procedure Split(S: Unbounded_String; First, Rest: out Unbounded_String) is
function Skip_Leading_Spaces(S: String) return String is
begin
if S="" then return "";
elsif S(S'First) = ' ' then return S(S'First+1 .. S'Last);
else return S;
end if;
end Skip_Leading_Spaces;
Str: String := Skip_Leading_Spaces(-S);
I: Positive := Str'First;
J: Natural;
begin
-- read nonspaces for First output param
J := I-1;
while J < Str'Last and then Str(J+1) /= ' ' loop
J := J + 1;
end loop;
First := + Str(I .. J);
-- write output param Rest
Rest := + Skip_Leading_Spaces(Str(J+1 .. Str'Last));
end Split;
procedure Print(S: String) is
begin
IO.Put_Line(S);
end Print;
package WW is new Word_Wrap(Print);
Wrapper: WW.Basic(Integer'Value(Ada.Command_Line.Argument(1)));
begin
while not IO.End_Of_File loop
Line := +IO.Get_Line;
if Line = +"" then
Wrapper.New_Paragraph;
Line := +IO.Get_Line;
end if;
while Line /= +"" loop
Split(Line, First => Word, Rest => Line);
Wrapper.Push_Word(-Word);
end loop;
end loop;
Wrapper.Finish;
end Wrap;</lang>
Output, set to 72 lines (with input picked by cut-and-paste from the task description):
Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way in your language. If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia. Show your routine working on a sample of text at two different wrap columns. Extra credit! Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm. If your language provides this, you get easy extra credit, but you must reference documentation indicating that the algorithm is something better than a simple minimimum length algorithm. If you have both basic and extra credit solutions, show an example where the two algorithms give different results.
Note that this solution properly deals with multi-paragraph inputs. For more sophisticated algorithms (the extra credit), one could derive a class Word_Wrap.<something> from Word_Wrap.Basic.
AWK
Basic word wrap.
<lang awk>function wordwrap_paragraph(p) {
if ( length(p) < 1 ) return split(p, words) spaceLeft = lineWidth line = words[1] delete words[1]
for (i = 1; i <= length(words); i++) {
word = words[i]
if ( (length(word) + 1) > spaceLeft ) {
print line
line = word
spaceLeft = lineWidth - length(word)
} else {
spaceLeft -= length(word) + 1
line = line " " word
}
}
print line
}
BEGIN {
lineWidth = width par = ""
}
/^[ \t]*$/ {
wordwrap_paragraph(par) par = ""
}
!/^[ \t]*$/ {
par = par " " $0
}
END {
wordwrap_paragraph(par)
}</lang>
To test it,
awk -f wordwrap.awk -v width=80 < text.txt
Bracmat
<lang bracmat>( str
$ ( "In olden times when wishing still helped one, there lived a king "
"whose daughters were all beautiful, but the youngest was so beautiful "
"that the sun itself, which has seen so much, was astonished whenever "
"it shone in her face. Close by the king's castle lay a great dark "
"forest, and under an old lime tree in the forest was a well, and when "
"the day was very warm, the king's child went out into the forest and "
"sat down by the side of the cool fountain, and when she was bored she "
"took a golden ball, and threw it up on high and caught it, and this "
"ball was her favorite plaything."
)
: ?Text
& ( wrap
= txt length line output q
. !arg:(?txt.?length)
& :?output
& whl
' ( @( str$!txt
: ?line
(" " %?lastword [?q " " ?txt&!q:~<!length)
)
& !lastword " " !txt:?txt
& !output !line \n:?output
)
& str$(!output !txt)
)
& out$(str$("72 columns:\n" wrap$(!Text.72))) & out$(str$("\n80 columns:\n" wrap$(!Text.80))) );</lang> Output:
72 columns: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was plaything. 80 columns: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and plaything.
C
<lang c>#include <stdio.h>
- include <stdlib.h>
- include <string.h>
- include <ctype.h>
/* nonsensical hyphens to make greedy wrapping method look bad */ const char *string = "In olden times when wishing still helped one, there lived a king " "whose daughters were all beautiful, but the youngest was so beautiful " "that the sun itself, which has seen so much, was astonished whenever " "it shone-in-her-face. Close-by-the-king's castle lay a great dark " "forest, and under an old lime-tree in the forest was a well, and when " "the day was very warm, the king's child went out into the forest and " "sat down by the side of the cool-fountain, and when she was bored she " "took a golden ball, and threw it up on high and caught it, and this " "ball was her favorite plaything.";
/* Each but the last of wrapped lines comes with some penalty as the square of the diff between line length and desired line length. If the line is longer than desired length, the penalty is multiplied by 100. This pretty much prohibits the wrapping routine from going over right margin. If is ok to exceed the margin just a little, something like 20 or 40 will do.
Knuth uses a per-paragraph penalty for line-breaking in TeX, which is-- unlike what I have here--probably bug-free.
- /
- define PENALTY_LONG 100
- define PENALTY_SHORT 1
typedef struct word_t { const char *s; int len; } *word;
word make_word_list(const char *s, int *n) { int max_n = 0; word words = 0;
*n = 0; while (1) { while (*s && isspace(*s)) s++; if (!*s) break;
if (*n >= max_n) { if (!(max_n *= 2)) max_n = 2; words = realloc(words, max_n * sizeof(*words)); } words[*n].s = s; while (*s && !isspace(*s)) s++; words[*n].len = s - words[*n].s; (*n) ++; }
return words; }
int greedy_wrap(word words, int count, int cols, int *breaks) { int score = 0, line, i, j, d;
i = j = line = 0; while (1) { if (i == count) { breaks[j++] = i; break; }
if (!line) { line = words[i++].len; continue; }
if (line + words[i].len < cols) { line += words[i++].len + 1; continue; }
breaks[j++] = i; if (i < count) { d = cols - line; if (d > 0) score += PENALTY_SHORT * d * d; else if (d < 0) score += PENALTY_LONG * d * d; }
line = 0; } breaks[j++] = 0;
return score; }
/* tries to make right margin more even; pretty sure there's an off-by-one bug here somewhere */ int balanced_wrap(word words, int count, int cols, int *breaks) { int *best = malloc(sizeof(int) * (count + 1));
/* do a greedy wrap to have some baseline score to work with, else we'll end up with O(2^N) behavior */ int best_score = greedy_wrap(words, count, cols, breaks);
void test_wrap(int line_no, int start, int score) { int line = 0, current_score = -1, d;
while (start <= count) { if (line) line ++; line += words[start++].len; d = cols - line; if (start < count || d < 0) { if (d > 0) current_score = score + PENALTY_SHORT * d * d; else current_score = score + PENALTY_LONG * d * d; } else { current_score = score; }
if (current_score >= best_score) { if (d <= 0) return; continue; }
best[line_no] = start; test_wrap(line_no + 1, start, current_score); } if (current_score >= 0 && current_score < best_score) { best_score = current_score; memcpy(breaks, best, sizeof(int) * (line_no)); } } test_wrap(0, 0, 0); free(best);
return best_score; }
void show_wrap(word list, int count, int *breaks) { int i, j; for (i = j = 0; i < count && breaks[i]; i++) { while (j < breaks[i]) { printf("%.*s", list[j].len, list[j].s); if (j < breaks[i] - 1) putchar(' '); j++; } if (breaks[i]) putchar('\n'); } }
int main(void) { int len, score, cols; word list = make_word_list(string, &len); int *breaks = malloc(sizeof(int) * (len + 1));
cols = 80; score = greedy_wrap(list, len, cols, breaks); printf("\n== greedy wrap at %d (score %d) ==\n\n", cols, score); show_wrap(list, len, breaks);
score = balanced_wrap(list, len, cols, breaks); printf("\n== balanced wrap at %d (score %d) ==\n\n", cols, score); show_wrap(list, len, breaks);
cols = 32;
score = greedy_wrap(list, len, cols, breaks);
printf("\n== greedy wrap at %d (score %d) ==\n\n", cols, score);
show_wrap(list, len, breaks);
score = balanced_wrap(list, len, cols, breaks); printf("\n== balanced wrap at %d (score %d) ==\n\n", cols, score); show_wrap(list, len, breaks);
return 0; }</lang>
C++
Basic task.
<lang cpp>#include <iostream>
- include <sstream>
- include <string>
const char *text = {
"In olden times when wishing still helped one, there lived a king " "whose daughters were all beautiful, but the youngest was so beautiful " "that the sun itself, which has seen so much, was astonished whenever " "it shone in her face. Close by the king's castle lay a great dark " "forest, and under an old lime tree in the forest was a well, and when " "the day was very warm, the king's child went out into the forest and " "sat down by the side of the cool fountain, and when she was bored she " "took a golden ball, and threw it up on high and caught it, and this " "ball was her favorite plaything."
};
std::string wrap(const char *text, size_t line_length = 72) {
std::istringstream words(text); std::ostringstream wrapped; std::string word;
if (words >> word) {
wrapped << word;
size_t space_left = line_length - word.length();
while (words >> word) {
if (space_left < word.length() + 1) {
wrapped << '\n' << word;
space_left = line_length - word.length();
} else {
wrapped << ' ' << word;
space_left -= word.length() + 1;
}
}
}
return wrapped.str();
}
int main() {
std::cout << "Wrapped at 72:\n" << wrap(text) << "\n\n"; std::cout << "Wrapped at 80:\n" << wrap(text, 80) << "\n";
}</lang>
- Output:
Wrapped at 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. Wrapped at 80: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
C#
Greedy algorithm: <lang csharp>namespace RosettaCode.WordWrap {
using System; using System.Collections.Generic;
internal static class Program
{
private const string LoremIpsum = @"
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh.";
private static void Main()
{
foreach (var lineWidth in new[] { 72, 80 })
{
Console.WriteLine(new string('-', lineWidth));
Console.WriteLine(Wrap(LoremIpsum, lineWidth));
}
}
private static string Wrap(string text, int lineWidth)
{
return string.Join(string.Empty,
Wrap(
text.Split(new char[0],
StringSplitOptions
.RemoveEmptyEntries),
lineWidth));
}
private static IEnumerable<string> Wrap(IEnumerable<string> words,
int lineWidth)
{
var currentWidth = 0;
foreach (var word in words)
{
if (currentWidth != 0)
{
if (currentWidth + word.Length < lineWidth)
{
currentWidth++;
yield return " ";
}
else
{
currentWidth = 0;
yield return Environment.NewLine;
}
}
currentWidth += word.Length;
yield return word;
}
}
}
}</lang> Output:
------------------------------------------------------------------------ Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh. -------------------------------------------------------------------------------- Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh.
Clojure
<lang Clojure>;; Wrap line naive version (defn wrap-line [size text]
(loop [left size line [] lines []
words (clojure.string/split text #"\s+")]
(if-let [word (first words)]
(let [wlen (count word)
spacing (if (== left size) "" " ")
alen (+ (count spacing) wlen)]
(if (<= alen left)
(recur (- left alen) (conj line spacing word) lines (next words))
(recur (- size wlen) [word] (conj lines (apply str line)) (next words))))
(when (seq line)
(conj lines (apply str line))))))</lang>
<lang Clojure>;; Wrap line base on regular expression (defn wrap-line [size text]
(re-seq (re-pattern (str ".{0," size "}\\s"))
(clojure.string/replace text #"\n" " ")))</lang>
Usage example : <lang Clojure>(def text "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.")
(doseq [line (wrap-line 72 text)]
(println line))</lang>
Output :
In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
D
Standard Version
<lang d>void main() {
immutable frog =
"In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.";
import std.stdio, std.string;
foreach (width; [72, 80])
writefln("Wrapped at %d:\n%s\n", width, frog.wrap(width));
}</lang>
- Output:
Wrapped at 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. Wrapped at 80: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
An Implementation
Basic algorithm. The text splitting is lazy.
<lang d>import std.algorithm;
string wrap(in string text, in int lineWidth) {
auto words = text.splitter;
if (words.empty) return null;
string wrapped = words.front;
words.popFront();
int spaceLeft = lineWidth - wrapped.length;
foreach (word; words)
if (word.length + 1 > spaceLeft) {
wrapped ~= "\n" ~ word;
spaceLeft = lineWidth - word.length;
} else {
wrapped ~= " " ~ word;
spaceLeft -= 1 + word.length;
}
return wrapped;
}
void main() {
immutable frog =
"In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.";
import std.stdio;
foreach (width; [72, 80])
writefln("Wrapped at %d:\n%s\n", width, frog.wrap(width));
}</lang>
- Output:
Wrapped at 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. Wrapped at 80: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
Erlang
<lang Erlang> -module( word_wrap ).
-export( [paragraph/2, task/0] ).
paragraph( String, Max_line_length ) -> Lines = lines( string:tokens(String, " "), Max_line_length ), string:join( Lines, "\n" ).
task() -> Paragraph = "Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way in your language. If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.", io:fwrite( "~s~n~n", [paragraph(Paragraph, 72)] ), io:fwrite( "~s~n~n", [paragraph(Paragraph, 80)] ).
lines( [Word | T], Max_line_length ) -> {Max_line_length, _Length, Last_line, Lines} = lists:foldl( fun lines_assemble/2, {Max_line_length, erlang:length(Word), Word, []}, T ), lists:reverse( [Last_line | Lines] ).
lines_assemble( Word, {Max, Line_length, Line, Acc} ) when erlang:length(Word) + Line_length > Max -> {Max, erlang:length(Word), Word, [Line | Acc]}; lines_assemble( Word, {Max, Line_length, Line, Acc} ) -> {Max, Line_length + 1 + erlang:length(Word), Line ++ " " ++ Word, Acc}. </lang>
- Output:
15> word_wrap:task(). Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way in your language. If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia. Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way in your language. If there is a way to do this that is built-in, trivial, or provided in a standard library, show that. Otherwise implement the minimum length greedy algorithm from Wikipedia.
F#
<lang fsharp>open System
let LoremIpsum = " Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh."
let Wrap words lineWidth =
let rec loop words currentWidth = seq {
match (words : string list) with
| word :: rest ->
let (stuff, pos) =
if currentWidth > 0 then
if currentWidth + word.Length < lineWidth then
(" ", (currentWidth + 1))
else
("\n", 0)
else ("", 0)
yield stuff + word
yield! loop rest (pos + word.Length)
| _ -> ()
}
loop words 0
[<EntryPoint>] let main argv =
for n in [72; 80] do
printfn "%s" (String('-', n))
let l = Seq.toList (LoremIpsum.Split((null:char[]), StringSplitOptions.RemoveEmptyEntries))
Wrap l n |> Seq.iter (printf "%s")
printfn ""
0</lang>
Output
------------------------------------------------------------------------ Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh. -------------------------------------------------------------------------------- Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas varius sapien vel purus hendrerit vehicula. Integer hendrerit viverra turpis, ac sagittis arcu pharetra id. Sed dapibus enim non dui posuere sit amet rhoncus tellus consectetur. Proin blandit lacus vitae nibh tincidunt cursus. Cum sociis natoque penatibus et magnis dis parturient montes, nascetur ridiculus mus. Nam tincidunt purus at tortor tincidunt et aliquam dui gravida. Nulla consectetur sem vel felis vulputate et imperdiet orci pharetra. Nam vel tortor nisi. Sed eget porta tortor. Aliquam suscipit lacus vel odio faucibus tempor. Sed ipsum est, condimentum eget eleifend ac, ultricies non dui. Integer tempus, nunc sed venenatis feugiat, augue orci pellentesque risus, nec pretium lacus enim eu nibh.
Forth
<lang forth>\ wrap text \ usage: gforth wrap.f in.txt 72
0. argc @ 1- arg >number 2drop drop constant maxLine
- .wrapped ( buf len -- )
begin dup maxLine > while over maxLine begin 1- 2dup + c@ bl = until dup 1+ >r begin 1- 2dup + c@ bl <> until 1+ type cr r> /string repeat type cr ;
- strip-nl ( buf len -- )
bounds do i c@ 10 = if bl i c! then loop ;
argc @ 2 - arg slurp-file 2dup strip-nl .wrapped bye</lang>
Go
Basic task, no extra credit. <lang go>package main
import (
"fmt" "strings"
)
func wrap(text string, lineWidth int) (wrapped string) {
words := strings.Fields(text)
if len(words) == 0 {
return
}
wrapped = words[0]
spaceLeft := lineWidth - len(wrapped)
for _, word := range words[1:] {
if len(word)+1 > spaceLeft {
wrapped += "\n" + word
spaceLeft = lineWidth - len(word)
} else {
wrapped += " " + word
spaceLeft -= 1 + len(word)
}
}
return
}
var frog = ` In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.`
func main() {
fmt.Println("wrapped at 80:")
fmt.Println(wrap(frog, 80))
fmt.Println("wrapped at 72:")
fmt.Println(wrap(frog, 72))
}</lang>
- Output:
wrapped at 80: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. wrapped at 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
Haskell
Greedy wrapping: <lang haskell>ss = "In olden times when wishing still helped one, there lived a king"
++"whose daughters were all beautiful, but the youngest was so beautiful" ++"that the sun itself, which has seen so much, was astonished whenever" ++"it shone in her face. Close by the king's castle lay a great dark" ++"forest, and under an old lime-tree in the forest was a well, and when" ++"the day was very warm, the king's child went out into the forest and" ++"sat down by the side of the cool fountain, and when she was bored she" ++"took a golden ball, and threw it up on high and caught it, and this" ++"ball was her favorite plaything."
wordwrap maxlen = (wrap_ 0) . words where wrap_ _ [] = "\n" wrap_ pos (w:ws) -- at line start: put down the word no matter what | pos == 0 = w ++ wrap_ (pos + lw) ws | pos + lw + 1 > maxlen = '\n':wrap_ 0 (w:ws) | otherwise = " " ++ w ++ wrap_ (pos + lw + 1) ws where lw = length w
main = do putStr $ wordwrap 72 ss putStr "\n" putStr $ wordwrap 32 ss</lang>
Icon and Unicon
The following works in both languages.
<lang unicon> procedure main(A)
ll := integer(A[1]) | 72 wordWrap(&input, ll)
end
procedure wordWrap(f, ll)
every (sep := "", s := "", w := words(f)) do
if w == "\n" then write(1(.s, s := sep := ""),"\n")
else if (*s + *w) >= ll then write(1(.s, s := w, sep := " "))
else (s ||:= .sep||("\n" ~== w), sep := " ")
if *s > 0 then write(s)
end
procedure words(f)
static wc
initial wc := &cset -- ' \t' # Loose definition of a 'word'...
while l := !f do {
l ? while tab(upto(wc)) do suspend tab(many(wc))\1
if *trim(l) = 0 then suspend "\n" # Paragraph boundary
}
end</lang>
Sample runs:
->ww <ww.icn
procedure main(A) ll := integer(A[1]) | 72 wordWrap(&input, ll) end
procedure wordWrap(f, ll) every (sep := "", s := "", w := words(f)) do
if w == "\n" then write(1(.s, s := sep := ""),"\n") else if (*s + *w) >=
ll then write(1(.s, s := w, sep := " ")) else (s ||:= .sep||("\n" ~==
w), sep := " ") if *s > 0 then write(s) end
procedure words(f) static wc initial wc := &cset -- ' \t' # Loose
definition of a 'word'... while l := !f do { l ? while tab(upto(wc)) do
suspend tab(many(wc))\1 if *trim(l) = 0 then suspend "\n" # Paragraph
boundary } end
->ww 50 <ww.icn
procedure main(A) ll := integer(A[1]) | 72
wordWrap(&input, ll) end
procedure wordWrap(f, ll) every (sep := "", s :=
"", w := words(f)) do if w == "\n" then
write(1(.s, s := sep := ""),"\n") else if (*s +
*w) >= ll then write(1(.s, s := w, sep := " "))
else (s ||:= .sep||("\n" ~== w), sep := " ") if *s
> 0 then write(s) end
procedure words(f) static wc initial wc := &cset
-- ' \t' # Loose definition of a 'word'... while l
:= !f do { l ? while tab(upto(wc)) do suspend
tab(many(wc))\1 if *trim(l) = 0 then suspend "\n"
# Paragraph boundary } end
->
J
Solution:<lang j>ww =: 75&$: : wrap
wrap =: (] turn edges) ,&' ' turn =: LF"_`]`[} edges =: (_1 + ] #~ 1 ,~ 2 >/\ |) [: +/\ #;.2</lang>
Example:<lang j> GA =: 'Four score and seven years ago, our forefathers brought forth upon this continent a new nation, dedicated to the proposition that all men were created equal.'
ww GA NB. Wrap at 75 chars by default
Four score and seven years ago, our forefathers brought forth upon this continent a new nation, dedicated to the proposition that all men were created equal.
20 ww GA NB. Specify different length
Four score and seven years ago, our forefathers brought forth upon this continent a new nation, dedicated to the proposition that all men were created equal.</lang>
Java
<lang java> package rosettacode;
import java.util.StringTokenizer;
public class WordWrap { int defaultLineWidth=80; int defaultSpaceWidth=1; void minNumLinesWrap(String text) { minNumLinesWrap(text,defaultLineWidth); } void minNumLinesWrap(String text,int LineWidth) { StringTokenizer st=new StringTokenizer(text); int SpaceLeft=LineWidth; int SpaceWidth=defaultSpaceWidth; while(st.hasMoreTokens()) { String word=st.nextToken(); if((word.length()+SpaceWidth)>SpaceLeft) { System.out.print("\n"+word+" "); SpaceLeft=LineWidth-word.length(); } else { System.out.print(word+" "); SpaceLeft-=(word.length()+SpaceWidth); } } } public static void main(String[] args) { WordWrap now=new WordWrap(); String wodehouse="Old Mr MacFarland (_said Henry_) started the place fifteen years ago. He was a widower with one son and what you might call half a daughter. That's to say, he had adopted her. Katie was her name, and she was the child of a dead friend of his. The son's name was Andy. A little freckled nipper he was when I first knew him--one of those silent kids that don't say much and have as much obstinacy in them as if they were mules. Many's the time, in them days, I've clumped him on the head and told him to do something; and he didn't run yelling to his pa, same as most kids would have done, but just said nothing and went on not doing whatever it was I had told him to do. That was the sort of disposition Andy had, and it grew on him. Why, when he came back from Oxford College the time the old man sent for him--what I'm going to tell you about soon--he had a jaw on him like the ram of a battleship. Katie was the kid for my money. I liked Katie. We all liked Katie."; System.out.println("DEFAULT:"); now.minNumLinesWrap(wodehouse); System.out.println("\n\nLINEWIDTH=120"); now.minNumLinesWrap(wodehouse,120); }
}
</lang>
Output:
DEFAULT: Old Mr MacFarland (_said Henry_) started the place fifteen years ago. He was a widower with one son and what you might call half a daughter. That's to say, he had adopted her. Katie was her name, and she was the child of a dead friend of his. The son's name was Andy. A little freckled nipper he was when I first knew him--one of those silent kids that don't say much and have as much obstinacy in them as if they were mules. Many's the time, in them days, I've clumped him on the head and told him to do something; and he didn't run yelling to his pa, same as most kids would have done, but just said nothing and went on not doing whatever it was I had told him to do. That was the sort of disposition Andy had, and it grew on him. Why, when he came back from Oxford College the time the old man sent for him--what I'm going to tell you about soon--he had a jaw on him like the ram of a battleship. Katie was the kid for my money. I liked Katie. We all liked Katie. LINEWIDTH=120 Old Mr MacFarland (_said Henry_) started the place fifteen years ago. He was a widower with one son and what you might call half a daughter. That's to say, he had adopted her. Katie was her name, and she was the child of a dead friend of his. The son's name was Andy. A little freckled nipper he was when I first knew him--one of those silent kids that don't say much and have as much obstinacy in them as if they were mules. Many's the time, in them days, I've clumped him on the head and told him to do something; and he didn't run yelling to his pa, same as most kids would have done, but just said nothing and went on not doing whatever it was I had told him to do. That was the sort of disposition Andy had, and it grew on him. Why, when he came back from Oxford College the time the old man sent for him--what I'm going to tell you about soon--he had a jaw on him like the ram of a battleship. Katie was the kid for my money. I liked Katie. We all liked Katie.
NetRexx
<lang NetRexx>/* NetRexx */ options replace format comments java crossref symbols
runSample(arg) return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /*
@see http://en.wikipedia.org/wiki/Word_wrap#Minimum_length
SpaceLeft := LineWidth
for each Word in Text
if (Width(Word) + SpaceWidth) > SpaceLeft
insert line break before Word in Text
SpaceLeft := LineWidth - Width(Word)
else
SpaceLeft := SpaceLeft - (Width(Word) + SpaceWidth)
*/
method wordWrap(text, lineWidth = 80) public static
if lineWidth > 0 then do
NL = '\n'
SP = ' '
wrapped =
spaceWidth = SP.length()
spaceLeft = lineWidth
loop w_ = 1 to text.words()
nextWord = text.word(w_)
if (nextWord.length() + spaceWidth) > spaceLeft then do
wrapped = wrapped || NL || nextWord
spaceLeft = lineWidth - nextWord.length()
end
else do
wrapped = wrapped || SP || nextWord
spaceLeft = spaceLeft - (nextWord.length() + spaceWidth)
end
end w_
end
else do
wrapped = text
end
return wrapped.strip() -- clean w/s from front & back
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method runSample(arg) public static
parse arg lineLen .
if lineLen = then lineLen = 80
text = getText()
wrappedLines = wordWrap(text, lineLen)
say 'Wrapping text at' lineLen 'characters'
say ('....+....|'.copies((lineLen + 9) % 10)).left(lineLen)
say wrappedLines
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method getText() public static
-- ....+....|....+....|....+....|....+....|....+....|....+....|
speech01 = -
'She should have died hereafter;' -
'There would have been a time for such a word.' -
'Tomorrow, and tomorrow, and tomorrow,' -
'Creeps in this petty pace from day to day,' -
'To the last syllable of recorded time;' -
'And all our yesterdays have lighted fools' -
'The way to dusty death. Out, out, brief candle!' -
'Lifes but a walking shadow, a poor player' -
'That struts and frets his hour upon the stage' -
'And then is heard no more. It is a tale' -
'Told by an idiot, full of sound and fury' -
'Signifying nothing.' -
-
'—-Macbeth (Act 5, Scene 5, lines 17-28)' -
return speech01
</lang>
- Output:
Wrapping text at 64 characters ....+....|....+....|....+....|....+....|....+....|....+....|.... She should have died hereafter; There would have been a time for such a word. Tomorrow, and tomorrow, and tomorrow, Creeps in this petty pace from day to day, To the last syllable of recorded time; And all our yesterdays have lighted fools The way to dusty death. Out, out, brief candle! Life's but a walking shadow, a poor player That struts and frets his hour upon the stage And then is heard no more. It is a tale Told by an idiot, full of sound and fury Signifying nothing. —-Macbeth (Act 5, Scene 5, lines 17-28) Wrapping text at 132 characters ....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|....+....|.. She should have died hereafter; There would have been a time for such a word. Tomorrow, and tomorrow, and tomorrow, Creeps in this petty pace from day to day, To the last syllable of recorded time; And all our yesterdays have lighted fools The way to dusty death. Out, out, brief candle! Life's but a walking shadow, a poor player That struts and frets his hour upon the stage And then is heard no more. It is a tale Told by an idiot, full of sound and fury Signifying nothing. —-Macbeth (Act 5, Scene 5, lines 17-28)
OCaml
<lang ocaml>#load "str.cma"
let txt = "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything."
let () =
let line_width = int_of_string Sys.argv.(1) in
let words = Str.split (Str.regexp "[ \n]+") txt in
let buf = Buffer.create 10 in
let _ =
List.fold_left (fun (width, sep) word ->
let wlen = String.length word in
let len = width + wlen + 1 in
if len > line_width then
begin
Buffer.add_char buf '\n';
Buffer.add_string buf word;
(wlen, " ")
end else begin
Buffer.add_string buf sep;
Buffer.add_string buf word;
(len, " ")
end
) (0, "") words
in
print_endline (Buffer.contents buf)</lang>
Testing:
$ ocaml word_wrap.ml 80 | wc -L 79 $ ocaml word_wrap.ml 72 | wc -L 72 $ ocaml word_wrap.ml 50 | wc -L 50
PARI/GP
<lang parigp>wrap(s,len)={
my(t="",cur);
s=Vec(s);
for(i=1,#s,
if(s[i]==" ",
if(cur>#t,
print1(" "t);
cur-=#t+1
,
print1("\n"t);
cur=len-#t
);
t=""
,
t=concat(t,s[i])
)
);
if(cur>#t,
print1(" "t)
,
print1("\n"t)
)
}; King="And so let freedom ring from the prodigious hilltops of New Hampshire; let freedom ring from the mighty mountains of New York; let freedom ring from the heightening Alleghenies of Pennsylvania; let freedom ring from the snow-capped Rockies of Colorado; let freedom ring from the curvaceous slopes of California. But not only that: let freedom ring from Stone Mountain of Georgia; let freedom ring from Lookout Mountain of Tennessee; let freedom ring from every hill and molehill of Mississippi. From every mountainside, let freedom ring."; wrap(King, 75) wrap(King, 50)</lang>
Output:
And so let freedom ring from the prodigious hilltops of New Hampshire; let freedom ring from the mighty mountains of New York; let freedom ring from the heightening Alleghenies of Pennsylvania; let freedom ring from the snow-capped Rockies of Colorado; let freedom ring from the curvaceous slopes of California. But not only that: let freedom ring from Stone Mountain of Georgia; let freedom ring from Lookout Mountain of Tennessee; let freedom ring from every hill and molehill of Mississippi. From every mountainside, let freedom ring. And so let freedom ring from the prodigious hilltops of New Hampshire; let freedom ring from the mighty mountains of New York; let freedom ring from the heightening Alleghenies of Pennsylvania; let freedom ring from the snow-capped Rockies of Colorado; let freedom ring from the curvaceous slopes of California. But not only that: let freedom ring from Stone Mountain of Georgia; let freedom ring from Lookout Mountain of Tennessee; let freedom ring from every hill and molehill of Mississippi. From every mountainside, let freedom ring.
Perl
Regex. Also showing degraded behavior on very long words: <lang perl>my $s = "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close-by-the-king's-castle-lay-a-great-dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.";
$s =~ s/\b\s+/ /g; $s =~ s/\s*$/\n\n/;
my $_ = $s; s/\s*(.{1,66})\s/$1\n/g, print;
$_ = $s; s/\s*(.{1,25})\s/$1\n/g, print;</lang>
Perl 6
<lang perl6>my $s = "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close-by-the-king's-castle-lay-a-great-dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.";
$s ~~ s:g/»\s+/ /; $s ~~ s/\s*$/\n\n/;
say $s.subst(/ \s* (. ** 1..66) \s /, -> $/ { "$0\n" }, :g); say $s.subst(/ \s* (. ** 1..25) \s /, -> $/ { "$0\n" }, :g);</lang>
PicoLisp
'wrap' is a built-in. <lang PicoLisp>: (prinl (wrap 12 (chop "The quick brown fox jumps over the lazy dog"))) The quick brown fox jumps over the lazy dog -> "The quick^Jbrown fox^Jjumps over^Jthe lazy dog"</lang>
Python
>>> import textwrap
>>> help(textwrap.fill)
Help on function fill in module textwrap:
fill(text, width=70, **kwargs)
Fill a single paragraph of text, returning a new string.
Reformat the single paragraph in 'text' to fit in lines of no more
than 'width' columns, and return a new string containing the entire
wrapped paragraph. As with wrap(), tabs are expanded and other
whitespace characters converted to space. See TextWrapper class for
available keyword args to customize wrapping behaviour.
>>> txt = '''\
Reformat the single paragraph in 'text' to fit in lines of no more
than 'width' columns, and return a new string containing the entire
wrapped paragraph. As with wrap(), tabs are expanded and other
whitespace characters converted to space. See TextWrapper class for
available keyword args to customize wrapping behaviour.'''
>>> print(textwrap.fill(txt, width=75))
Reformat the single paragraph in 'text' to fit in lines of no more than
'width' columns, and return a new string containing the entire wrapped
paragraph. As with wrap(), tabs are expanded and other whitespace
characters converted to space. See TextWrapper class for available keyword
args to customize wrapping behaviour.
>>> print(textwrap.fill(txt, width=45))
Reformat the single paragraph in 'text' to
fit in lines of no more than 'width' columns,
and return a new string containing the entire
wrapped paragraph. As with wrap(), tabs are
expanded and other whitespace characters
converted to space. See TextWrapper class
for available keyword args to customize
wrapping behaviour.
>>> print(textwrap.fill(txt, width=85))
Reformat the single paragraph in 'text' to fit in lines of no more than 'width'
columns, and return a new string containing the entire wrapped paragraph. As with
wrap(), tabs are expanded and other whitespace characters converted to space. See
TextWrapper class for available keyword args to customize wrapping behaviour.
>>>
Racket
Using a library function: <lang Racket>
- lang at-exp racket
(require scribble/text/wrap) (define text
@(λ xs (regexp-replace* #rx" *\n *" (string-append* xs) " ")){
In olden times when wishing still helped one, there lived a king whose
daughters were all beautiful, but the youngest was so beautiful that the
sun itself, which has seen so much, was astonished whenever it shone in her
face. Close by the king's castle lay a great dark forest, and under an old
lime-tree in the forest was a well, and when the day was very warm, the
king's child went out into the forest and sat down by the side of the cool
fountain, and when she was bored she took a golden ball, and threw it up on
high and caught it, and this ball was her favorite plaything.})
(for-each displayln (wrap-line text 60)) </lang>
Explicit (and simple) implementation: <lang racket>
- lang racket
(define (wrap words width)
(define (maybe-cons xs xss)
(if (empty? xs) xss (cons xs xss)))
(match/values
(for/fold ([lines '()] [line '()] [left width]) ([w words])
(define n (string-length w))
(cond
[(> n width) ; word longer than line => line on its own
(values (cons (list w) (maybe-cons line lines)) '() width)]
[(> n left) ; not enough space left => new line
(values (cons line lines) (list w) (- width n 1))]
[else
(values lines (cons w line) (- left n 1))]))
[(lines line _)
(apply string-append
(for/list ([line (reverse (cons line lines))])
(string-join line #:after-last "\n")))]))
- Usage
(wrap (string-split text) 70) </lang>
REXX
version 0
This version was the original (of version 1) and has no error checking and only does left-margin justification. <lang rexx>/*REXX pgm reads a file and displays it (with word wrap to the screen). */ parse arg iFID width /*get optional arguments from CL.*/ @= /*nullify the text (so far). */
do j=0 while lines(iFID)\==0 /*read from the file until E-O-F.*/
@=@ linein(iFID) /*append the file's text to @ */
end /*j*/
$=
do k=1 for words(@); x=word(@,k) /*parse until text (@) exhausted.*/
_=$ x /*append it to the money and see.*/
if length(_)>width then do /*words exceeded the width? */
say $ /*display what we got so far. */
_=x /*overflow for the next line. */
end
$=_ /*append this word to the output.*/
end /*k*/
if $\== then say $ /*handle any residual words. */
/*stick a fork in it, we're done.*/</lang>
output is the same as version 1 using the Left option (the default).
version 1
The input for this program is in a file (named LAWS.TXT).
The default width of the output is the current terminal width (normally, this would be the window's width).
If the terminal width (or window's width) is indeterminable, then 80 is used.
The width can be expressed as a percentage (i.e.: 50%) which signifies to use ½ of the terminal's width).
No hyphenation (or de-hyphenation) is attempted.
Words longer than the width of the output are acceptable and are shown (with no truncation), a simple change could be made to issue a notification.
Some rudimentary error checking is performed.
Types of word wrapping (justification) are (only the first character is significant):
Center: ◄centered►
Right: ────────►right margin
Left: left margin◄─────────
Both: ◄───both margins────►
(Left is the default.) <lang rexx>/*REXX pgm reads a file and displays it (with word wrap to the screen). */ parse arg iFID width justify _ . /*get optional CL args.*/ if iFID= |iFID==',' then iFID ='LAWS.TXT' /*default input file ID*/ if width==|width==',' then width=linesize() /*Default? Use linesize*/ if width==0 then width=80 /*indeterminable width.*/ if right(width,1)=='%' then do /*handle % of width. */
width=translate(width,,'%') /*remove the %*/
width=linesize() * translate(width,,"%")%100
end
if justify==|justify==',' then justify='Left' /*Default? Use LEFT */ just=left(justify,1) /*only use first char of JUSTIFY.*/ upper just /*be able to handle mixed case. */ if pos(just,'BCLR')==0 then call err "JUSTIFY (3rd arg) is illegal:" justify if _\== then call err "too many arguments specified." _ if \datatype(width,'W') then call err "WIDTH (2nd arg) isn't an integer:" width @= /*nullify the text (so far). */
do j=0 while lines(iFID)\==0 /*read from the file until E-O-F.*/
@=@ linein(iFID) /*append the file's text to @ */
end /*j*/
if j==0 then call err 'file' iFID "not found." if @= then call err 'file' iFID "is empty." $=
do k=1 for words(@); x=word(@,k) /*parse until text (@) exhausted.*/ _=$ x /*append it to the money and see.*/ if length(_)>width then call tell /*word(s) exceeded the width? */ $=_ /*the new words are OK so far. */ end /*k*/
call tell /*handle any residual words. */ exit /*stick a fork in it, we're done.*/ /*──────────────────────────────────ERR subroutine──────────────────────*/ err: say; say '***error!***'; say; say arg(1); say; say; exit 13 /*──────────────────────────────────TELL subroutine─────────────────────*/ tell: if $== then return /*first word may be too long. */ w=max(width,length($)) /*don't truncate very long words.*/
select
when just=='B' then $=justify($,w) /*◄────both────►*/
when just=='C' then $= center($,w) /* ◄centered► */
when just=='L' then $= strip($) /*left ◄────────*/
when just=='R' then $= right($,w) /*──────► right */
end /*select*/
say $ /*show and tell, or write──►file?*/ _=x /*handle any word overflow. */ return /*go back and keep truckin'. */</lang> The input file:
────────── Computer programming laws ──────────
The Primal Scenario -or- Basic Datum of Experience:
∙ Systems in general work poorly or not at all.
∙ Nothing complicated works.
∙ Complicated systems seldom exceed 5% efficiency.
∙ There is always a fly in the ointment.
The Fundamental Theorem:
∙ New systems generate new problems.
Occam's Razor:
∙ Systems should not be unnecessarily multiplied.
The Law of Conservation of Energy:
∙ The total amount of energy in the universe is constant.
∙ Systems operate by redistributing energy into different forms and into accumulations of different sizes.
Laws of Growth:
∙ Systems tend to grow, and as they grow, they encroach.
The Big-Bang Theorem of Systems-Cosmology:
∙ Systems tend to expand to fill the known universe.
Parkinson's Extended Law:
∙ The system itself tends to expand at 5-6% per annum.
The Generalized Uncertainty Principle:
∙ Systems display antics.
∙ Complicated systems produce unexpected outcomes.
∙ The total behavior of large systems cannot be predicted.
The Non-Addivity Theorem of Systems-Behavior -or- Climax Design Theorem:
∙ A large system, produced by expanding the dimensions of a smaller system, does not behave like the smaller system.
LeChateliers's Principle:
∙ Complex systems tend to oppose their own proper function.
∙ Systems get in the way.
∙ The system always kicks back.
∙ Positive feedback is dangerous.
Functionary's Falsity:
∙ People in systems do not do what the system says they are doing.
∙ The function performed by a system is not operationally identical to the function of the same name performed by a man.
∙ A function performed by a larger system is not operationally identical to the function of the same name performed by a smaller system.
The Fundamental Law of Administrative Workings:
∙ Things are what they are reported to be.
∙ The real world is whatever is reported to the system.
∙ If it isn't official; it didn't happen.
∙ If it's made in Detriot, it must be an automobile.
∙ A system is no better than its sensory organs.
∙ To those within a system, the outside reality tends to pale and disappear.
∙ Systems attract systems-people.
∙ For every human system, there is a type of person adapted to thrive on it or in it.
∙ The bigger the system, the narrower and more specialized the interface with individuals.
Administrator's Anxiety:
∙ Pushing on the systems doesn't help. It just makes things worse.
∙ A complex system cannot be "made" to work. It either works or it doesn't.
∙ A simple system, designed from scratch, sometimes works.
∙ A simple system may or may not work.
∙ Some complex systems actually work.
∙ If a system is working, leave it alone.
∙ A complex system that works is invariably found to have evolved from a simple system that works.
∙ A complex system designed from scratch never works and cannot be patched up to make it work. You have to start over, beginning with a working simple system.
∙ Programs never run the first time.
∙ Complex programs never run.
∙ Anything worth doing once will probably have to be done twice.
The Functional indeterminancy Theorem:
∙ In complex systems, malfunction and even total nonfunction may not be detectable for long periods, if ever.
The Kantian Hypothesis -or- Know-Nothing Theorem:
∙ Large complex systems are beyond human capacity to evaluate.
The Newtonian Lay of Systems-Inertia:
∙ A system that performs a certain way will continue to operate in that way regardless of the need of of changed conditions.
∙ A system continues to do its thing, regardless of need.
∙ Systems develop goals of their own the instant they come into being.
∙ Intrasystem goals come first.
Failure-Mode Theorems:
∙ Complex systems usually operate in failure mode.
∙ A complex system can fail in a infinite number of ways.
∙ If anything can go wrong, it will.
∙ The mode of failure of a complex system cannot ordinarily be predicted from its structure.
∙ The crucial variables are discovered by accident.
∙ The larger the system, the greater the probability of unexpected failure.
∙ "Success" or "function" in any system may be failure in the larger or smaller systems to which the system is connected.
∙ In setting up a new system, tread softly. You may be disturbing another system that is actually working.
The Fail-Safe Theorem:
∙ When a fail-safe system fails, it fails by failing to fail safe.
∙ Complex systems tend to produce complex responses (not solutions) to problems.
∙ Great advances are not produced by systems designed to produce great advances.
∙ Loose systems last longer and work better.
∙ Efficient systems are dangerous to themselves and to others.
The Vector Theory of Systems:
∙ Systems run better when designed to run downhill.
∙ Systems aligned with human motivational vectors will sometimes work. Systems opposing such vectors work poorly or not at all.
Advanced Systems Theories:
∙ Everything is a system.
∙ Everything is a part of a larger system.
∙ The universe is infinitely systematized, both upward [larger systems] and downward [smaller systems].
∙ All systems are infinitely complex. (The illusion of simplicity comes from focusing attention on one or a few variables.)
∙ Parameters are variables travelling under an assumed name.
Output when specifying: , 155
────────── Computer programming laws ────────── The Primal Scenario -or- Basic Datum of Experience: ∙ Systems in general work poorly or not at all. ∙ Nothing complicated works. ∙ Complicated systems seldom exceed 5% efficiency. ∙ There is always a fly in the ointment. The Fundamental Theorem: ∙ New systems generate new problems. Occam's Razor: ∙ Systems should not be unnecessarily multiplied. The Law of Conservation of Energy: ∙ The total amount of energy in the universe is constant. ∙ Systems operate by redistributing energy into different forms and into accumulations of different sizes. Laws of Growth: ∙ Systems tend to grow, and as they grow, they encroach. The Big-Bang Theorem of Systems-Cosmology: ∙ Systems tend to expand to fill the known universe. Parkinson's Extended Law: ∙ The system itself tends to expand at 5-6% per annum. The Generalized Uncertainty Principle: ∙ Systems display antics. ∙ Complicated systems produce unexpected outcomes. ∙ The total behavior of large systems cannot be predicted. The Non-Addivity Theorem of Systems-Behavior -or- Climax Design Theorem: ∙ A large system, produced by expanding the dimensions of a smaller system, does not behave like the smaller system. LeChateliers's Principle: ∙ Complex systems tend to oppose their own proper function. ∙ Systems get in the way. ∙ The system always kicks back. ∙ Positive feedback is dangerous. Functionary's Falsity: ∙ People in systems do not do what the system says they are doing. ∙ The function performed by a system is not operationally identical to the function of the same name performed by a man. ∙ A function performed by a larger system is not operationally identical to the function of the same name performed by a smaller system. The Fundamental Law of Administrative Workings: ∙ Things are what they are reported to be. ∙ The real world is whatever is reported to the system. ∙ If it isn't official; it didn't happen. ∙ If it's made in Detriot, it must be an automobile. ∙ A system is no better than its sensory organs. ∙ To those within a system, the outside reality tends to pale and disappear. ∙ Systems attract systems-people. ∙ For every human system, there is a type of person adapted to thrive on it or in it. ∙ The bigger the system, the narrower and more specialized the interface with individuals. Administrator's Anxiety: ∙ Pushing on the systems doesn't help. It just makes things worse. ∙ A complex system cannot be "made" to work. It either works or it doesn't. ∙ A simple system, designed from scratch, sometimes works. ∙ A simple system may or may not work. ∙ Some complex systems actually work. ∙ If a system is working, leave it alone. ∙ A complex system that works is invariably found to have evolved from a simple system that works. ∙ A complex system designed from scratch never works and cannot be patched up to make it work. You have to start over, beginning with a working simple system. ∙ Programs never run the first time. ∙ Complex programs never run. ∙ Anything worth doing once will probably have to be done twice. The Functional indeterminancy Theorem: ∙ In complex systems, malfunction and even total nonfunction may not be detectable for long periods, if ever. The Kantian Hypothesis -or- Know-Nothing Theorem: ∙ Large complex systems are beyond human capacity to evaluate. The Newtonian Lay of Systems-Inertia: ∙ A system that performs a certain way will continue to operate in that way regardless of the need of of changed conditions. ∙ A system continues to do its thing, regardless of need. ∙ Systems develop goals of their own the instant they come into being. ∙ Intrasystem goals come first. Failure-Mode Theorems: ∙ Complex systems usually operate in failure mode. ∙ A complex system can fail in a infinite number of ways. ∙ If anything can go wrong, it will. ∙ The mode of failure of a complex system cannot ordinarily be predicted from its structure. ∙ The crucial variables are discovered by accident. ∙ The larger the system, the greater the probability of unexpected failure. ∙ "Success" or "function" in any system may be failure in the larger or smaller systems to which the system is connected. ∙ In setting up a new system, tread softly. You may be disturbing another system that is actually working. The Fail-Safe Theorem: ∙ When a fail-safe system fails, it fails by failing to fail safe. ∙ Complex systems tend to produce complex responses (not solutions) to problems. ∙ Great advances are not produced by systems designed to produce great advances. ∙ Loose systems last longer and work better. ∙ Efficient systems are dangerous to themselves and to others. The Vector Theory of Systems: ∙ Systems run better when designed to run downhill. ∙ Systems aligned with human motivational vectors will sometimes work. Systems opposing such vectors work poorly or not at all. Advanced Systems Theories: ∙ Everything is a system. ∙ Everything is a part of a larger system. ∙ The universe is infinitely systematized, both upward [larger systems] and downward [smaller systems]. ∙ All systems are infinitely complex. (The illusion of simplicity comes from focusing attention on one or a few variables.) ∙ Parameters are variables travelling under an assumed name.
Output when specifying: , 76
────────── Computer programming laws ────────── The Primal Scenario -or- Basic Datum of Experience: ∙ Systems in general work poorly or not at all. ∙ Nothing complicated works. ∙ Complicated systems seldom exceed 5% efficiency. ∙ There is always a fly in the ointment. The Fundamental Theorem: ∙ New systems generate new problems. Occam's Razor: ∙ Systems should not be unnecessarily multiplied. The Law of Conservation of Energy: ∙ The total amount of energy in the universe is constant. ∙ Systems operate by redistributing energy into different forms and into accumulations of different sizes. Laws of Growth: ∙ Systems tend to grow, and as they grow, they encroach. The Big-Bang Theorem of Systems-Cosmology: ∙ Systems tend to expand to fill the known universe. Parkinson's Extended Law: ∙ The system itself tends to expand at 5-6% per annum. The Generalized Uncertainty Principle: ∙ Systems display antics. ∙ Complicated systems produce unexpected outcomes. ∙ The total behavior of large systems cannot be predicted. The Non-Addivity Theorem of Systems-Behavior -or- Climax Design Theorem: ∙ A large system, produced by expanding the dimensions of a smaller system, does not behave like the smaller system. LeChateliers's Principle: ∙ Complex systems tend to oppose their own proper function. ∙ Systems get in the way. ∙ The system always kicks back. ∙ Positive feedback is dangerous. Functionary's Falsity: ∙ People in systems do not do what the system says they are doing. ∙ The function performed by a system is not operationally identical to the function of the same name performed by a man. ∙ A function performed by a larger system is not operationally identical to the function of the same name performed by a smaller system. The Fundamental Law of Administrative Workings: ∙ Things are what they are reported to be. ∙ The real world is whatever is reported to the system. ∙ If it isn't official; it didn't happen. ∙ If it's made in Detriot, it must be an automobile. ∙ A system is no better than its sensory organs. ∙ To those within a system, the outside reality tends to pale and disappear. ∙ Systems attract systems-people. ∙ For every human system, there is a type of person adapted to thrive on it or in it. ∙ The bigger the system, the narrower and more specialized the interface with individuals. Administrator's Anxiety: ∙ Pushing on the systems doesn't help. It just makes things worse. ∙ A complex system cannot be "made" to work. It either works or it doesn't. ∙ A simple system, designed from scratch, sometimes works. ∙ A simple system may or may not work. ∙ Some complex systems actually work. ∙ If a system is working, leave it alone. ∙ A complex system that works is invariably found to have evolved from a simple system that works. ∙ A complex system designed from scratch never works and cannot be patched up to make it work. You have to start over, beginning with a working simple system. ∙ Programs never run the first time. ∙ Complex programs never run. ∙ Anything worth doing once will probably have to be done twice. The Functional indeterminancy Theorem: ∙ In complex systems, malfunction and even total nonfunction may not be detectable for long periods, if ever. The Kantian Hypothesis -or- Know-Nothing Theorem: ∙ Large complex systems are beyond human capacity to evaluate. The Newtonian Lay of Systems-Inertia: ∙ A system that performs a certain way will continue to operate in that way regardless of the need of of changed conditions. ∙ A system continues to do its thing, regardless of need. ∙ Systems develop goals of their own the instant they come into being. ∙ Intrasystem goals come first. Failure-Mode Theorems: ∙ Complex systems usually operate in failure mode. ∙ A complex system can fail in a infinite number of ways. ∙ If anything can go wrong, it will. ∙ The mode of failure of a complex system cannot ordinarily be predicted from its structure. ∙ The crucial variables are discovered by accident. ∙ The larger the system, the greater the probability of unexpected failure. ∙ "Success" or "function" in any system may be failure in the larger or smaller systems to which the system is connected. ∙ In setting up a new system, tread softly. You may be disturbing another system that is actually working. The Fail-Safe Theorem: ∙ When a fail-safe system fails, it fails by failing to fail safe. ∙ Complex systems tend to produce complex responses (not solutions) to problems. ∙ Great advances are not produced by systems designed to produce great advances. ∙ Loose systems last longer and work better. ∙ Efficient systems are dangerous to themselves and to others. The Vector Theory of Systems: ∙ Systems run better when designed to run downhill. ∙ Systems aligned with human motivational vectors will sometimes work. Systems opposing such vectors work poorly or not at all. Advanced Systems Theories: ∙ Everything is a system. ∙ Everything is a part of a larger system. ∙ The universe is infinitely systematized, both upward [larger systems] and downward [smaller systems]. ∙ All systems are infinitely complex. (The illusion of simplicity comes from focusing attention on one or a few variables.) ∙ Parameters are variables travelling under an assumed name.
Output [justified] when specifying: , 70 both
────────── Computer programming laws ────────── The Primal Scenario -or- Basic Datum of Experience: ∙ Systems in general work poorly or not at all. ∙ Nothing complicated works. ∙ Complicated systems seldom exceed 5% efficiency. ∙ There is always a fly in the ointment. The Fundamental Theorem: ∙ New systems generate new problems. Occam's Razor: ∙ Systems should not be unnecessarily multiplied. The Law of Conservation of Energy: ∙ The total amount of energy in the universe is constant. ∙ Systems operate by redistributing energy into different forms and into accumulations of different sizes. Laws of Growth: ∙ Systems tend to grow, and as they grow, they encroach. The Big-Bang Theorem of Systems-Cosmology: ∙ Systems tend to expand to fill the known universe. Parkinson's Extended Law: ∙ The system itself tends to expand at 5-6% per annum. The Generalized Uncertainty Principle: ∙ Systems display antics. ∙ Complicated systems produce unexpected outcomes. ∙ The total behavior of large systems cannot be predicted. The Non-Addivity Theorem of Systems-Behavior -or- Climax Design Theorem: ∙ A large system, produced by expanding the dimensions of a smaller system, does not behave like the smaller system. LeChateliers's Principle: ∙ Complex systems tend to oppose their own proper function. ∙ Systems get in the way. ∙ The system always kicks back. ∙ Positive feedback is dangerous. Functionary's Falsity: ∙ People in systems do not do what the system says they are doing. ∙ The function performed by a system is not operationally identical to the function of the same name performed by a man. ∙ A function performed by a larger system is not operationally identical to the function of the same name performed by a smaller system. The Fundamental Law of Administrative Workings: ∙ Things are what they are reported to be. ∙ The real world is whatever is reported to the system. ∙ If it isn't official; it didn't happen. ∙ If it's made in Detriot, it must be an automobile. ∙ A system is no better than its sensory organs. ∙ To those within a system, the outside reality tends to pale and disappear. ∙ Systems attract systems-people. ∙ For every human system, there is a type of person adapted to thrive on it or in it. ∙ The bigger the system, the narrower and more specialized the interface with individuals. Administrator's Anxiety: ∙ Pushing on the systems doesn't help. It just makes things worse. ∙ A complex system cannot be "made" to work. It either works or it doesn't. ∙ A simple system, designed from scratch, sometimes works. ∙ A simple system may or may not work. ∙ Some complex systems actually work. ∙ If a system is working, leave it alone. ∙ A complex system that works is invariably found to have evolved from a simple system that works. ∙ A complex system designed from scratch never works and cannot be patched up to make it work. You have to start over, beginning with a working simple system. ∙ Programs never run the first time. ∙ Complex programs never run. ∙ Anything worth doing once will probably have to be done twice. The Functional indeterminancy Theorem: ∙ In complex systems, malfunction and even total nonfunction may not be detectable for long periods, if ever. The Kantian Hypothesis -or- Know-Nothing Theorem: ∙ Large complex systems are beyond human capacity to evaluate. The Newtonian Lay of Systems-Inertia: ∙ A system that performs a certain way will continue to operate in that way regardless of the need of of changed conditions. ∙ A system continues to do its thing, regardless of need. ∙ Systems develop goals of their own the instant they come into being. ∙ Intrasystem goals come first. Failure-Mode Theorems: ∙ Complex systems usually operate in failure mode. ∙ A complex system can fail in a infinite number of ways. ∙ If anything can go wrong, it will. ∙ The mode of failure of a complex system cannot ordinarily be predicted from its structure. ∙ The crucial variables are discovered by accident. ∙ The larger the system, the greater the probability of unexpected failure. ∙ "Success" or "function" in any system may be failure in the larger or smaller systems to which the system is connected. ∙ In setting up a new system, tread softly. You may be disturbing another system that is actually working. The Fail-Safe Theorem: ∙ When a fail-safe system fails, it fails by failing to fail safe. ∙ Complex systems tend to produce complex responses (not solutions) to problems. ∙ Great advances are not produced by systems designed to produce great advances. ∙ Loose systems last longer and work better. ∙ Efficient systems are dangerous to themselves and to others. The Vector Theory of Systems: ∙ Systems run better when designed to run downhill. ∙ Systems aligned with human motivational vectors will sometimes work. Systems opposing such vectors work poorly or not at all. Advanced Systems Theories: ∙ Everything is a system. ∙ Everything is a part of a larger system. ∙ The universe is infinitely systematized, both upward [larger systems] and downward [smaller systems]. ∙ All systems are infinitely complex. (The illusion of simplicity comes from focusing attention on one or a few variables.) ∙ Parameters are variables travelling under an assumed name.
version 2
<lang rexx>/* REXX ***************************************************************
- 20.08.2013 Walter Pachl "my way"
- /
Parse Arg w oid=w'.xxx'; 'erase' oid Call o left(copies('123456789.',20),w) s='She should have died hereafter;' ,
'There would have been a time for such a word.' , 'Tomorrow, and tomorrow, and tomorrow, and so on'
Call ow s Exit ow:
Parse Arg s
s=s' '
Do While length(s)>w
Do i=w+1 to 1 by -1
If substr(s,i,1)= Then Leave
End
If i=0 Then
p=pos(' ',s)
Else
p=i
Call o left(s,p)
s=substr(s,p+1)
End
If s> Then
Call o s
Return
o:Return lineout(oid,arg(1))</lang> Output for widths 72 and 9
123456789.123456789.123456789.123456789.123456789.123456789.123456789.12 She should have died hereafter; There would have been a time for such a word. Tomorrow, and tomorrow, and tomorrow, and so on 123456789 She should have died hereafter; There would have been a time for such a word. Tomorrow, and tomorrow, and tomorrow, and so on
Ruby
<lang ruby>class String
def wrap(width)
txt = gsub(/\s+/, " ")
para = []
i = 0
while i < txt.length
j = i + width
j -= 1 while txt[j] != " "
para << txt[i .. j-1]
i = j + 1
end
para.join("\n")
end
end
text = <<END In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. END
[72,80].each do |w|
puts "." * w puts text.wrap(w)
end</lang>
outputs
........................................................................ In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. ................................................................................ In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
Run BASIC
Word Wrap style for different browsers. This automatically adjusts the text if the browser window is stretched in any direction <lang runbasic>doc$ = "In olden times when wishing still helped one, there lived a king ";_ "whose daughters were all beautiful, but the youngest was so beautiful ";_ "that the sun itself, which has seen so much, was astonished whenever ";_ "it shone in her face."
wrap$ = " style='white-space: pre-wrap;white-space: -moz-pre-wrap;white-space: -pre-wrap;";_
"white-space: -o-pre-wrap;word-wrap: break-word'"
html "
<tr" + wrap$ +" valign=top>" html "| " + doc$ + " | " + doc$ + " |
"</lang>
output will adjust as you stretch the browser and maintain a 60 to 40 ratio of the width of the screen.
---------- at 60%----------------------- | -------- at 40%---------------------- In olden times when wishing still helped one, there lived a king | In olden times when wishing still helped whose daughters were all beautiful, but the youngest was so | one, there lived a king whose daughters beautiful that the sun itself, which has seen so much, was | were all beautiful, but the youngest was astonished whenever it shone in her face. | so beautiful that the sun itself, which | has seen so much, was astonished whenever | it shone in her face.
Without Browser <lang runbasic>doc$ = "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything."
input "Width"; width ' user specifies width
while word$(doc$,i + 1," ") <> ""
i = i + 1 thisWord$ = word$(doc$,i," ") + " " if word$(thisWord$,2,chr$(13)) <> "" then thisWord$ = word$(thisWord$,2,chr$(13)) + " " ' strip the <CR> if len(docOut$) + len(thisWord$) > width then print docOut$ docOut$ = "" end if docOut$ = docOut$ + thisWord$
wend print docOut$</lang>
Seed7
<lang seed7>$ include "seed7_05.s7i";
const func string: wrap (in string: aText, in integer: lineWidth) is func
result
var string: wrapped is "";
local
var array string: words is 0 times "";
var string: word is "";
var integer: spaceLeft is 0;
begin
words := split(aText, " ");
if length(words) <> 0 then
wrapped := words[1];
words := words[2 ..];
spaceLeft := lineWidth - length(wrapped);
for word range words do
if length(word) + 1 > spaceLeft then
wrapped &:= "\n" & word;
spaceLeft := lineWidth - length(word);
else
wrapped &:= " " & word;
spaceLeft -:= 1 + length(word);
end if;
end for;
end if;
end func;
const proc: main is func
local
const string: frog is "In olden times when wishing still helped one, there lived \
\a king whose daughters were all beautiful, but the youngest was so beautiful \
\that the sun itself, which has seen so much, was astonished whenever it \
\shone in her face. Close by the king's castle lay a great dark forest, and \
\under an old lime-tree in the forest was a well, and when the day was very \
\warm, the king's child went out into the forest and sat down by the side of \
\the cool fountain, and when she was bored she took a golden ball, and threw \
\it up on high and caught it, and this ball was her favorite plaything.";
var integer: width is 0;
begin
for width range [] (72, 80) do
writeln("Wrapped at " <& width <& ":");
writeln(wrap(frog, width));
end for;
end func;</lang>
- Output:
Wrapped at 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. Wrapped at 80: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
Tcl
Using a simple greedy algorithm to wrap the same text as used in the Go solution. Note that it assumes that the line length is longer than the longest word length. <lang tcl>package require Tcl 8.5
proc wrapParagraph {n text} {
regsub -all {\s+} [string trim $text] " " text
set RE "^(.{1,$n})(?:\\s+(.*))?$"
for {set result ""} {[regexp $RE $text -> line text]} {} {
append result $line "\n"
} return [string trimright $result "\n"]
}
set txt \ "In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything."
puts "[string repeat - 80]" puts [wrapParagraph 80 $txt] puts "[string repeat - 72]" puts [wrapParagraph 72 $txt]</lang>
- Output:
-------------------------------------------------------------------------------- In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. ------------------------------------------------------------------------ In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.
TPP
The text presentation program automatically provides word wrap:
<lang tpp> The kings youngest daughter was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face.</lang>
TUSCRIPT
<lang tuscript> $$ MODE TUSCRIPT text="In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything."
ERROR/STOP CREATE ("text",seq-E,-std-)
length=80 line=REPEAT ("-",length) FILE "text" = line firstline=nextlines="" wrappedtext=FORMAT(text,length,firstline,nextlines) FILE "text" = wrappedtext
length=72 line=REPEAT ("-",length) FILE "text" = line firstline=CONCAT ("Length ",length,": ") wrappedtext=FORMAT(text,length,firstline,nextlines) FILE "text" = wrappedtext </lang> Output:
-------------------------------------------------------------------------------- In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything. ------------------------------------------------------------------------ Length 72: In olden times when wishing still helped one, there lived a king whose daughters were all beautiful, but the youngest was so beautiful that the sun itself, which has seen so much, was astonished whenever it shone in her face. Close by the king's castle lay a great dark forest, and under an old lime-tree in the forest was a well, and when the day was very warm, the king's child went out into the forest and sat down by the side of the cool fountain, and when she was bored she took a golden ball, and threw it up on high and caught it, and this ball was her favorite plaything.