Brace expansion using ranges
Write and test a function which expands one or more Unix-style numeric and alphabetic range braces embedded in a larger string.
Brace expansion using ranges is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
Task[|_}}%20*%2F%20 edit]
Specification
The brace strings used by Unix shells permit expansion of both:
- Recursive comma-separated lists (covered by the related task: Brace_expansion, and can be ignored here)
- ordered numeric and alphabetic ranges, which are the object of this task.
The general pattern of brace ranges is:
{<START>..<END>}
and, in more recent shells:
{<START>..<END>..<INCR>}
(See https://wiki.bash-hackers.org/syntax/expansion/brace)
Expandable ranges of this kind can be ascending or descending:
simpleNumber{1..3}.txt
simpleAlpha-{Z..X}.txt
and may have a third INCR element specifying ordinal intervals larger than one. The increment value can be preceded by a - minus sign, but not by a + sign.
The effect of the minus sign is to always to reverse the natural order suggested by the START and END values.
Any level of zero-padding used in either the START or END value of a numeric range is adopted in the expansions.
steppedDownAndPadded-{10..00..5}.txt
minusSignFlipsSequence {030..20..-5}.txt
A single string may contain more than one expansion range:
combined-{Q..P}{2..1}.txt
Alphabetic range values are limited to a single character for START and END but these characters are not confined to the ASCII alphabet.
emoji{🌵..🌶}{🌽..🌾}etc
Unmatched braces are simply ignored, as are empty braces, and braces which contain no range (or list).
li{teral
rangeless{}empty
rangeless{random}string
Tests
Generate and display here the expansion of each of the nine example lines shown above.
The JavaScript implementation below uses parser combinators, aiming to encode a more or less full and legible description of the
<PREAMBLE><AMBLE><POSTSCRIPT>
range brace grammar, but you should use any resource that suggests itself in your language, including parser libraries.
(The grammar of range expansion, unlike that of nested list expansion, is not recursive, so even regular expressions should prove serviceable here).
The output of the JS implementation, which aims to match the brace expansion behaviour of the default zsh shell on macOS Catalina is:
simpleNumberRising{1..3}.txt ->
simpleNumberRising1.txt
simpleNumberRising2.txt
simpleNumberRising3.txt
simpleAlphaDescending-{Z..X}.txt ->
simpleAlphaDescending-Z.txt
simpleAlphaDescending-Y.txt
simpleAlphaDescending-X.txt
steppedDownAndPadded-{10..00..5}.txt ->
steppedDownAndPadded-10.txt
steppedDownAndPadded-05.txt
steppedDownAndPadded-00.txt
minusSignFlipsSequence {030..20..-5}.txt ->
minusSignFlipsSequence 020.txt
minusSignFlipsSequence 025.txt
minusSignFlipsSequence 030.txt
combined-{Q..P}{2..1}.txt ->
combined-Q2.txt
combined-Q1.txt
combined-P2.txt
combined-P1.txt
emoji{🌵..🌶}{🌽..🌾}etc ->
emoji🌵🌽etc
emoji🌵🌾etc
emoji🌶🌽etc
emoji🌶🌾etc
li{teral ->
li{teral
rangeless{}empty ->
rangeless{}empty
rangeless{random}string ->
rangeless{random}string
- Related tasks
JavaScript
<lang javascript>(() => {
'use strict';
// --------------- BRACE-RANGE EXPANSION ---------------
// braceExpandWithRange :: String -> [String]
const braceExpandWithRange = s => {
// A list containing either the expansions
// of s, if there are any, or s itself.
const
expansions = parse(some(
braceRangeExpansion()
))(s);
return 0 < expansions.length ? (() => {
const [parsed, residue] = Array.from(
expansions[0]
);
return suffixAdd(
parsed.reduce(
uncurry(suffixMultiply),
[]
)
)([residue.join()])
})() : [s];
};
// ----------- BRACE-RANGE EXPANSION PARSER ------------
// braceRangeExpansion :: [String]
const braceRangeExpansion = () =>
// List of strings expanded from a
// a unix shell {<START>..<END>} or
// {<START>..<END>..<INCR>} expression.
// See https://wiki.bash-hackers.org/syntax/expansion/brace
fmapP(([preamble, amble, postscript]) =>
suffixAdd(
suffixMultiply(preamble)(amble)
)(postscript)
)(sequenceP([
affixLeaf(),
fmapP(xs => [xs])(
between(char('{'))(char('}'))(
altP(
numericSequence()
)(
characterSequence()
)
)
),
affixLeaf()
]));
// ----------------------- TESTS -----------------------
// main :: IO ()
const main = () => {
const tests = [
'simpleNumberRising{1..3}.txt',
'simpleAlphaDescending-{Z..X}.txt',
'steppedDownAndPadded-{10..00..5}.txt',
'minusSignFlipsSequence {030..20..-5}.txt',
'combined-{Q..P}{2..1}.txt',
'emoji{🌵..🌶}{🌽..🌾}etc',
'li{teral',
'rangeless{}empty',
'rangeless{random}string'
];
return tests.map(
s => s + ' -> ' + '\n\t' + (
braceExpandWithRange(s).join('\n\t')
)
).join('\n\n');
};
// ----------- BRACE-RANGE COMPONENT PARSERS -----------
// affixLeaf :: () -> Parser String
const affixLeaf = () =>
// A sequence of literal (non-syntactic)
// characters before or after a pair of braces.
fmapP(cs => [
[cs.join()]
])(
many(choice([noneOf('{\\'), escape()]))
);
// characterSequence :: () -> Parser [Char]
const characterSequence = () =>
// A rising or descending alphabetic
// sequence of characters.
fmapP(ab => {
const [from, to] = ab;
return from !== to ? (
enumFromThenToChar(from)(
(from < to ? succ : pred)(from)
)(to)
) : [from];
})(
ordinalRange(satisfy(
c => !'0123456789'.includes(c)
))
);
// enumerationList :: ((Bool, String), String) ->
// ((Bool, String), String) ->
// ((Bool, String), String) -> [String]
const enumerationList = triple => {
// An ordered list of numeric strings either
// rising or descending, in numeric order, and
// possibly prefixed with zeros.
const
w = padWidth(triple[0][1])(triple[1][1]),
[from, to, by] = triple.map(
sn => (sn[0] ? negate : identity)(
parseInt(sn[1])
)
);
return map(
compose(justifyRight(w)('0'), str)
)(
0 > by ? (
enumFromThenTo(to)(to - by)(from)
) : enumFromThenTo(from)(
from + (to >= from ? by : -by)
)(to)
);
};
// numericPart :: () -> Parser (Bool, String)
const numericPart = () =>
// The Bool is True if the string is
// negated by a leading '-'
// The String component contains the digits.
bindP(
option()(char('-'))
)(sign => bindP(
some(digit())
)(ds => pureP(
Tuple(Boolean(sign))(concat(ds))
)));
// numericSequence :: () -> Parser [String]
const numericSequence = () =>
// An ascending or descending sequence
// of numeric strings, possibly
// left-padded with zeros.
fmapP(enumerationList)(sequenceP([
ordinalRange(numericPart()),
numericStep()
]));
// numericStep :: () -> Parser (Bool, Int)
const numericStep = () =>
// The size of increment for a numeric
// series. Descending if the Bool is True.
// Defaults to (False, 1).
option(Tuple(false)(1))(
bindP(
string('..')
)(_ => bindP(
numericPart()
)(pureP))
);
// ordinalRange :: Enum a =>
// Parser a -> Parser (a, a)
const ordinalRange = p =>
// A pair of enumerable values of the same
// type, representing the start and end of
// a range.
bindP(
p
)(from => bindP(
string('..')
)(_ => bindP(
p
)(compose(pureP, append([from])))));
// padWidth :: String -> String -> Int
const padWidth = cs =>
// The length of the first of cs and cs1 to
// start with a zero. Otherwise (if neither
// starts with a zero) then 0.
cs1 => [cs, cs1].reduce(
(a, x) => (0 < a) || (1 > x.length) ? (
a
) : '0' !== x[0] ? a : x.length,
0
);
// suffixAdd :: [String] -> [String] -> [String]
const suffixAdd = xs =>
ys => xs.flatMap(
flip(append)(ys)
);
// suffixMultiply :: [String] -> [String] -> [String]
const suffixMultiply = xs =>
apList(xs.map(append));
// ------------ GENERIC PARSER COMBINATORS -------------
// Parser :: String -> [(a, String)] -> Parser a
const Parser = f =>
// A function lifted into a Parser object.
({
type: 'Parser',
parser: f
});
// altP (<|>) :: Parser a -> Parser a -> Parser a
const altP = p =>
// p, or q if p doesn't match.
q => Parser(s => {
const xs = parse(p)(s);
return 0 < xs.length ? (
xs
) : parse(q)(s);
});
// apP <*> :: Parser (a -> b) -> Parser a -> Parser b
const apP = pf =>
// A new parser obtained by the application
// of a Parser-wrapped function,
// to a Parser-wrapped value.
p => Parser(
s => parse(pf)(s).flatMap(
vr => parse(
fmapP(vr[0])(p)
)(vr[1])
)
);
// between :: Parser open -> Parser close ->
// Parser a -> Parser a
const between = pOpen =>
// A version of p which matches between
// pOpen and pClose (both discarded).
pClose => p => bindP(
pOpen
)(_ => bindP(
p
)(x => bindP(
pClose
)(_ => pureP(x))));
// bindP (>>=) :: Parser a ->
// (a -> Parser b) -> Parser b
const bindP = p =>
// A new parser obtained by the application of
// a function to a Parser-wrapped value.
// The function must enrich its output, lifting it
// into a new Parser.
// Allows for the nesting of parsers.
f => Parser(
s => parse(p)(s).flatMap(
tpl => parse(f(tpl[0]))(tpl[1])
)
);
// char :: Char -> Parser Char
const char = x =>
// A particular single character.
satisfy(c => x == c);
// choice :: [Parser a] -> Parser a
const choice = ps =>
// A parser constructed from a
// (left to right) list of alternatives.
ps.reduce(uncurry(altP), emptyP());
// digit :: Parser Char
const digit = () =>
// A single digit.
satisfy(isDigit);
// emptyP :: () -> Parser a
const emptyP = () =>
// The empty list.
Parser(_ => []);
// escape :: Parser String
const escape = () =>
fmapP(xs => xs.join())(
sequenceP([char('\\'), item()])
);
// fmapP :: (a -> b) -> Parser a -> Parser b
const fmapP = f =>
// A new parser derived by the structure-preserving
// application of f to the value in p.
p => Parser(
s => parse(p)(s).flatMap(
vr => Tuple(f(vr[0]))(vr[1])
)
);
// item :: () -> Parser Char
const item = () =>
// A single character.
Parser(
s => 0 < s.length ? [
Tuple(s[0])(
s.slice(1)
)
] : []
);
// liftA2P :: (a -> b -> c) ->
// Parser a -> Parser b -> Parser c
const liftA2P = op =>
// The binary function op, lifted
// to a function over two parsers.
p => apP(fmapP(op)(p));
// many :: Parser a -> Parser [a]
const many = p => {
// Zero or more instances of p.
// Lifts a parser for a simple type of value
// to a parser for a list of such values.
const some_p = p =>
liftA2P(
x => xs => [x].concat(xs)
)(p)(many(p));
return Parser(
s => parse(
0 < s.length ? (
altP(some_p(p))(pureP([]))
) : pureP([])
)(s)
);
};
// noneOf :: String -> Parser Char
const noneOf = s =>
// Any character not found in the
// exclusion string.
satisfy(c => !s.includes(c));
// option :: a -> Parser a -> Parser a
const option = x =>
// Either p or the default value x.
p => altP(p)(pureP(x));
// parse :: Parser a -> String -> [(a, String)]
const parse = p =>
// The result of parsing s with p.
s => {
//showLog('s', s)
return p.parser([...s]);
};
// pureP :: a -> Parser a
const pureP = x =>
// The value x lifted, unchanged,
// into the Parser monad.
Parser(s => [Tuple(x)(s)]);
// satisfy :: (Char -> Bool) -> Parser Char
const satisfy = test =>
// Any character for which the
// given predicate returns true.
Parser(
s => 0 < s.length ? (
test(s[0]) ? [
Tuple(s[0])(s.slice(1))
] : []
) : []
);
// sepBy1 :: Parser a -> Parser b -> Parser [a]
const sepBy1 = p =>
// One or more occurrences of p, as
// separated by (discarded) instances of sep.
sep => bindP(
p
)(x => bindP(
many(bindP(
sep
)(_ => bindP(
p
)(pureP))))(
xs => pureP([x].concat(xs))));
// sequenceP :: [Parser a] -> Parser [a]
const sequenceP = ps =>
// A single parser for a list of values, derived
// from a list of parsers for single values.
Parser(
s => ps.reduce(
(a, q) => a.flatMap(
vr => parse(q)(snd(vr)).flatMap(
first(xs => fst(vr).concat(xs))
)
),
[Tuple([])(s)]
)
);
// some :: Parser a -> Parser [a]
const some = p => {
// One or more instances of p.
// Lifts a parser for a simple type of value
// to a parser for a list of such values.
const many_p = p =>
altP(some(p))(pureP([]));
return Parser(
s => parse(
liftA2P(
x => xs => [x].concat(xs)
)(p)(many_p(p))
)(s)
);
};
// string :: String -> Parser String
const string = s =>
// A particular string.
fmapP(cs => cs.join())(
sequenceP([...s].map(char))
);
// ----------------- GENERAL FUNCTIONS -----------------
// Tuple (,) :: a -> b -> (a, b)
const Tuple = a =>
b => ({
type: 'Tuple',
'0': a,
'1': b,
length: 2
});
// apList (<*>) :: [(a -> b)] -> [a] -> [b]
const apList = fs =>
// The sequential application of each of a list
// of functions to each of a list of values.
// apList([x => 2 * x, x => 20 + x])([1, 2, 3])
// -> [2, 4, 6, 21, 22, 23]
xs => fs.flatMap(f => xs.map(f));
// append (++) :: [a] -> [a] -> [a]
const append = xs =>
// A list obtained by the
// concatenation of two others.
ys => xs.concat(ys);
// compose (<<<) :: (b -> c) -> (a -> b) -> a -> c
const compose = (...fs) =>
// A function defined by the right-to-left
// composition of all the functions in fs.
fs.reduce(
(f, g) => x => f(g(x)),
x => x
);
// concat :: a -> [a] // concat :: [String] -> String const concat = xs => ( ys => 0 < ys.length ? ( ys.every(Array.isArray) ? ( [] ) : ).concat(...ys) : ys )(list(xs));
// enumFromThenTo :: Int -> Int -> Int -> [Int]
const enumFromThenTo = x1 =>
x2 => y => {
const d = x2 - x1;
return Array.from({
length: Math.floor(y - x2) / d + 2
}, (_, i) => x1 + (d * i));
};
// enumFromThenToChar :: Char -> Char -> Char -> [Char]
const enumFromThenToChar = x1 =>
x2 => y => {
const [i1, i2, iY] = Array.from([x1, x2, y])
.map(x => x.codePointAt(0)),
d = i2 - i1;
return Array.from({
length: (Math.floor(iY - i2) / d) + 2
}, (_, i) => String.fromCodePoint(i1 + (d * i)));
};
// first :: (a -> b) -> ((a, c) -> (b, c))
const first = f =>
// A simple function lifted to one which applies
// to a tuple, transforming only its first item.
xy => Tuple(f(xy[0]))(
xy[1]
);
// flip :: (a -> b -> c) -> b -> a -> c
const flip = op =>
// The binary function op with
// its arguments reversed.
1 < op.length ? (
(a, b) => op(b, a)
) : (x => y => op(y)(x));
// fst :: (a, b) -> a
const fst = tpl =>
// First member of a pair.
tpl[0];
// fromEnum :: Enum a => a -> Int
const fromEnum = x =>
typeof x !== 'string' ? (
x.constructor === Object ? (
x.value
) : parseInt(Number(x))
) : x.codePointAt(0);
// identity :: a -> a
const identity = x =>
// The identity function. (`id`, in Haskell)
x;
// isAlpha :: Char -> Bool
const isAlpha = c =>
/[A-Za-z\u00C0-\u00FF]/.test(c);
// isDigit :: Char -> Bool
const isDigit = c => {
const n = c.codePointAt(0);
return 48 <= n && 57 >= n;
};
// justifyRight :: Int -> Char -> String -> String
const justifyRight = n =>
// The string s, preceded by enough padding (with
// the character c) to reach the string length n.
c => s => n > s.length ? (
s.padStart(n, c)
) : s;
// list :: StringOrArrayLike b => b -> [a]
const list = xs =>
// xs itself, if it is an Array,
// or an Array derived from xs.
Array.isArray(xs) ? (
xs
) : Array.from(xs || []);
// map :: (a -> b) -> [a] -> [b]
const map = f =>
// The list obtained by applying f
// to each element of xs.
// (The image of xs under f).
xs => [...xs].map(f);
// maxBound :: a -> a
const maxBound = x => {
const e = x.enum;
return Boolean(e) ? (
e[e[x.max]]
) : {
'number': Number.MAX_SAFE_INTEGER,
'string': String.fromCodePoint(0x10FFFF),
'boolean': true
} [typeof x];
};
// minBound :: a -> a
const minBound = x => {
const e = x.enum;
return Boolean(e) ? (
e[e[0]]
) : {
'number': Number.MIN_SAFE_INTEGER,
'string': String.fromCodePoint(0),
'boolean': false
} [typeof x];
};
// negate :: Num -> Num
const negate = n =>
-n;
// pred :: Enum a => a -> a
const pred = x => {
const t = typeof x;
return 'number' !== t ? (() => {
const [i, mn] = [x, minBound(x)].map(fromEnum);
return i > mn ? (
toEnum(x)(i - 1)
) : Error('succ :: enum out of range.');
})() : x > Number.MIN_SAFE_INTEGER ? (
x - 1
) : Error('succ :: Num out of range.');
};
// showLog :: a -> IO ()
const showLog = (...args) =>
console.log(
args
.map(JSON.stringify)
.join(' -> ')
);
// snd :: (a, b) -> b
const snd = tpl =>
// Second member of a pair.
tpl[1];
// str :: a -> String
const str = x =>
Array.isArray(x) && x.every(
v => ('string' === typeof v) && (1 === v.length)
) ? (
x.join()
) : x.toString();
// succ :: Enum a => a -> a
const succ = x => {
const t = typeof x;
return 'number' !== t ? (() => {
const [i, mx] = [x, maxBound(x)].map(fromEnum);
return i < mx ? (
toEnum(x)(1 + i)
) : Error('succ :: enum out of range.')
})() : x < Number.MAX_SAFE_INTEGER ? (
1 + x
) : Error('succ :: Num out of range.')
};
// toEnum :: a -> Int -> a
const toEnum = e =>
// The first argument is a sample of the type
// allowing the function to make the right mapping
x => ({
'number': Number,
'string': String.fromCodePoint,
'boolean': Boolean,
'object': v => e.min + v
} [typeof e])(x);
// uncurry :: (a -> b -> c) -> ((a, b) -> c)
const uncurry = f =>
// A function over a pair, derived
// from a curried function.
function () {
const
args = arguments,
xy = Boolean(args.length % 2) ? (
args[0]
) : args;
return f(xy[0])(xy[1]);
};
// MAIN --- return main();
})();</lang>
- Output:
simpleNumberRising{1..3}.txt ->
simpleNumberRising1.txt
simpleNumberRising2.txt
simpleNumberRising3.txt
simpleAlphaDescending-{Z..X}.txt ->
simpleAlphaDescending-Z.txt
simpleAlphaDescending-Y.txt
simpleAlphaDescending-X.txt
steppedDownAndPadded-{10..00..5}.txt ->
steppedDownAndPadded-10.txt
steppedDownAndPadded-05.txt
steppedDownAndPadded-00.txt
minusSignFlipsSequence {030..20..-5}.txt ->
minusSignFlipsSequence 020.txt
minusSignFlipsSequence 025.txt
minusSignFlipsSequence 030.txt
combined-{Q..P}{2..1}.txt ->
combined-Q2.txt
combined-Q1.txt
combined-P2.txt
combined-P1.txt
emoji{🌵..🌶}{🌽..🌾}etc ->
emoji🌵🌽etc
emoji🌵🌾etc
emoji🌶🌽etc
emoji🌶🌾etc
li{teral ->
li{teral
rangeless{}empty ->
rangeless{}empty
rangeless{random}string ->
rangeless{random}string
Julia
Julia currently does not handle certain trigraphs in strings correctly, such as 🌶, so that test is omitted. <lang julia>padzeros(str) = (len = length(str)) > 1 && str[1] == '0' ? len : 0
function ranged(str)
rang = split(str[2:end-1], "..")
delta = length(rang) > 2 ? parse(Int, rang[3]) : 1
if delta < 0
rang[1], rang[2], delta = rang[2], rang[1], -delta
end
if '0' <= rang[1][1] <= '9' || rang[1][1] == '-'
x, y = parse(Int, rang[1]), parse(Int, rang[2])
pad = max(padzeros(rang[1]), padzeros(rang[2]))
return [string(x, pad=pad) for x in range(x, step=(x < y) ? delta : -delta, stop=y)]
else
x, y, z = rang[1][end], rang[2][end], rang[1][1:end-1]
return [z * string(x) for x in range(x, step=(x < y) ? delta : -delta, stop=y)]
end
end
function splatrange(s)
m = match(r"([^\{]*)(\{[^}]+\.\.[^\}]+\})(.*)", s)
m == nothing && return [s]
c = m.captures
return vec([a * b for b in splatrange(c[3]), a in [c[1] * x for x in ranged(c[2])]])
end
for test in [
"simpleNumberRising{1..3}.txt",
"simpleAlphaDescending-{Z..X}.txt",
"steppedDownAndPadded-{10..00..5}.txt",
"minusSignFlipsSequence {030..20..-5}.txt",
"combined-{Q..P}{2..1}.txt",
"li{teral",
"rangeless{}empty",
"rangeless{random}string",
]
println(test, "->\n", [" " * x * "\n" for x in splatrange(test)]...)
end
</lang>
- Output:
simpleNumberRising{1..3}.txt->
simpleNumberRising1.txt
simpleNumberRising2.txt
simpleNumberRising3.txt
simpleAlphaDescending-{Z..X}.txt->
simpleAlphaDescending-Z.txt
simpleAlphaDescending-Y.txt
simpleAlphaDescending-X.txt
steppedDownAndPadded-{10..00..5}.txt->
steppedDownAndPadded-10.txt
steppedDownAndPadded-05.txt
steppedDownAndPadded-00.txt
minusSignFlipsSequence {030..20..-5}.txt->
minusSignFlipsSequence 020.txt
minusSignFlipsSequence 025.txt
minusSignFlipsSequence 030.txt
combined-{Q..P}{2..1}.txt->
combined-Q2.txt
combined-Q1.txt
combined-P2.txt
combined-P1.txt
li{teral->
li{teral
rangeless{}empty->
rangeless{}empty
rangeless{random}string->
rangeless{random}string
Raku
Also implements some of the string list functions described on the bash-hackers page.
<lang perl6>my $range = rx/ '{' $<start> = <-[.]>+? '..' $<end> = <-[.]>+? ['..' $<incr> = ['-'?\d+] ]? '}' /; my $list = rx/ ^ $<prefix> = .*? '{' (<-[,}]>+) +%% ',' '}' $<postfix> = .* $/;
sub expand (Str $string) {
my @return = $string;
if $string ~~ $range {
quietly my ($start, $end, $incr) = $/<start end incr>».Str;
$incr ||= 1;
($end, $start) = $start, $end if $incr < 0;
$incr.=abs;
if try +$start ~~ Numeric and +$end ~~ Numeric {
$incr = - $incr if $start > $end;
my ($sl, $el) = 0, 0;
$sl = $start.chars if $start.starts-with('0');
$el = $end.chars if $end.starts-with('0');
my @this = $start < $end ?? (+$start, * + $incr …^ * > +$end) !! (+$start, * + $incr …^ * < +$end);
@return = @this.map: { $string.subst($range, sprintf("%{'0' ~ max $sl, $el}d", $_) ) }
}
elsif $start !~~ /\d/ and $end !~~ /\d/ {
$incr = - $incr if $start gt $end;
my @this = $start lt $end ?? ($start, (*.ord + $incr).chr …^ * gt $end) !! ($start, (*.ord + $incr).chr …^ * lt $end);
@return = @this.map: { $string.subst($range, sprintf("%s", $_) ) }
}
}
if $string ~~ $list {
my $these = $/[0]».Str;
my ($prefix, $postfix) = $/<prefix postfix>».Str;
if ($prefix ~ $postfix).chars {
@return = $these.map: { $string.subst($list, $prefix ~ $_ ~ $postfix) } if $these.elems > 1
}
else {
@return = $these.join: ' '
}
}
@return
}
for qww<
# Required tests
simpleNumberRising{1..3}.txt
simpleAlphaDescending-{Z..X}.txt
steppedDownAndPadded-{10..00..5}.txt
minusSignFlipsSequence{030..20..-5}.txt
combined-{Q..P}{2..1}.txt
emoji{🌵..🌶}{🌽..🌾}etc
li{teral
rangeless{}empty
rangeless{random}string
# Test some other features
# Emoji lists
emoji{☃,☄}{★,🇺🇸,☆}lists
# Doesn't end exactly on endpoint
'stops after endpoint-{02..10..3}.txt'
# Simple list
'simple {I,want,my,money,back} list'
# Prefix, list
_{I,want,my,money,back}
# Postfix, list
{I,want,my,money,back}!
# List, no prefix, postfix
{I,want,my,money,back}
# fail by design
'alphanumeric mix{a..1}.txt'
> -> $test {
say "$test ->";
my @strings = expand $test;
my $cnt = -1;
while $cnt != +@strings {
$cnt = +@strings;
@strings.=map: { |.&expand }
}
say (' ' xx * Z~ @strings).join: "\n";
say ;
} </lang>
- Output:
simpleNumberRising{1..3}.txt ->
simpleNumberRising1.txt
simpleNumberRising2.txt
simpleNumberRising3.txt
simpleAlphaDescending-{Z..X}.txt ->
simpleAlphaDescending-Z.txt
simpleAlphaDescending-Y.txt
simpleAlphaDescending-X.txt
steppedDownAndPadded-{10..00..5}.txt ->
steppedDownAndPadded-10.txt
steppedDownAndPadded-05.txt
steppedDownAndPadded-00.txt
minusSignFlipsSequence{030..20..-5}.txt ->
minusSignFlipsSequence020.txt
minusSignFlipsSequence025.txt
minusSignFlipsSequence030.txt
combined-{Q..P}{2..1}.txt ->
combined-Q2.txt
combined-Q1.txt
combined-P2.txt
combined-P1.txt
emoji{🌵..🌶}{🌽..🌾}etc ->
emoji🌵🌽etc
emoji🌵🌾etc
emoji🌶🌽etc
emoji🌶🌾etc
li{teral ->
li{teral
rangeless{}empty ->
rangeless{}empty
rangeless{random}string ->
rangeless{random}string
emoji{☃,☄}{★,🇺🇸,☆}lists ->
emoji☃★lists
emoji☃🇺🇸lists
emoji☃☆lists
emoji☄★lists
emoji☄🇺🇸lists
emoji☄☆lists
stops after endpoint-{02..10..3}.txt ->
stops after endpoint-02.txt
stops after endpoint-05.txt
stops after endpoint-08.txt
simple {I,want,my,money,back} list ->
simple I list
simple want list
simple my list
simple money list
simple back list
_{I,want,my,money,back} ->
_I
_want
_my
_money
_back
{I,want,my,money,back}! ->
I!
want!
my!
money!
back!
{I,want,my,money,back} ->
I want my money back
alphanumeric mix{a..1}.txt ->
alphanumeric mix{a..1}.txt
Wren
Added a further example to test mixed number/alpha ranges which apparently are not expanded. <lang ecmascript>import "/fmt" for Fmt
var parseRange = Fn.new { |r|
if (r == "") return ["{}"] // rangeless, empty
var sp = r.split("..")
if (sp.count == 1) return ["{%(r)}"] // rangeless, random value
var sta = sp[0]
var end = sp[1]
var inc = (sp.count == 2) ? "1" : sp[2]
var n1 = Num.fromString(sta)
var n2 = Num.fromString(end)
var n3 = Num.fromString(inc)
if (!n3) return ["{%(r)}"] // increment isn't a number
var numeric = n1 && n2
if (!numeric) {
if ((n1 && !n2) || (!n1 && n2)) return ["{%(r)}"] // mixed numeric/alpha not expanded
if (sta.count != 1 || end.count != 1) return ["{%(r)}"] // start/end are not both single alpha
n1 = sta.codePoints[0]
n2 = end.codePoints[0]
}
var width = 1
if (numeric) width = (sta.count < end.count) ? end.count : sta.count
if (n3 == 0) return (numeric) ? [Fmt.dz(width, n1)] : [sta] // zero increment
var res = []
var asc = n1 < n2
if (n3 < 0) {
asc = !asc
var t = n1
n1 = n2
n2 = t
n3 = -n3
}
var i = n1
if (asc) {
while (i <= n2) {
res.add( (numeric) ? Fmt.dz(width, i) : String.fromCodePoint(i) )
i = i + n3
}
} else {
while (i >= n2) {
res.add(( numeric) ? Fmt.dz(width, i) : String.fromCodePoint(i) )
i = i - n3
}
}
return res
}
var rangeExpand = Fn.new { |s|
var res = [""]
var rng = ""
var inRng = false
for (c in s) {
if (c == "{" && !inRng) {
inRng = true
rng = ""
} else if (c == "}" && inRng) {
var rngRes = parseRange.call(rng)
var rngCount = rngRes.count
var res2 = []
for (i in 0...res.count) {
for (j in 0...rngCount) res2.add(res[i] + rngRes[j])
}
res = res2
inRng = false
} else if (inRng) {
rng = rng + c
} else {
for (i in 0...res.count) res[i] = res[i] + c
}
}
if (inRng) for (i in 0...res.count) res[i] = res[i] + "{" + rng // unmatched braces
return res
}
var examples = [
"simpleNumberRising{1..3}.txt",
"simpleAlphaDescending-{Z..X}.txt",
"steppedDownAndPadded-{10..00..5}.txt",
"minusSignFlipsSequence {030..20..-5}.txt",
"combined-{Q..P}{2..1}.txt",
"emoji{🌵..🌶}{🌽..🌾}etc",
"li{teral",
"rangeless{}empty",
"rangeless{random}string",
"mixedNumberAlpha{5..k}"
]
for (s in examples) {
System.write("%(s) ->\n ")
var res = rangeExpand.call(s)
System.print(res.join("\n "))
System.print()
}</lang>
- Output:
simpleNumberRising{1..3}.txt ->
simpleNumberRising1.txt
simpleNumberRising2.txt
simpleNumberRising3.txt
simpleAlphaDescending-{Z..X}.txt ->
simpleAlphaDescending-Z.txt
simpleAlphaDescending-Y.txt
simpleAlphaDescending-X.txt
steppedDownAndPadded-{10..00..5}.txt ->
steppedDownAndPadded-10.txt
steppedDownAndPadded-05.txt
steppedDownAndPadded-00.txt
minusSignFlipsSequence {030..20..-5}.txt ->
minusSignFlipsSequence 020.txt
minusSignFlipsSequence 025.txt
minusSignFlipsSequence 030.txt
combined-{Q..P}{2..1}.txt ->
combined-Q2.txt
combined-Q1.txt
combined-P2.txt
combined-P1.txt
emoji{🌵..🌶}{🌽..🌾}etc ->
emoji🌵🌽etc
emoji🌵🌾etc
emoji🌶🌽etc
emoji🌶🌾etc
li{teral ->
li{teral
rangeless{}empty ->
rangeless{}empty
rangeless{random}string ->
rangeless{random}string
mixedNumberAlpha{5..k} ->
mixedNumberAlpha{5..k}