String interpolation (included)

Given a string and defined variables or values, string interpolation is the replacement of defined character sequences in the string by values or variable values.

For example, given an original string of "Mary had a X lamb.", a value of "big", and if the language replaces X in its interpolation routine, then the result of its interpolation would be the string "Mary had a big lamb".

(Languages usually include an infrequently used character or sequence of characters to indicate what is to be replaced such as "%", or "#" rather than "X").

Task

Use your languages inbuilt string interpolation abilities to interpolate a string missing the text "little" which is held in a variable, to produce the output string "Mary had a little lamb".
If possible, give links to further documentation on your languages string interpolation features.

Note: The task is not to create a string interpolation routine, but to show a language's built-in capability.

Other tasks related to string operations:

Metrics

Counting

Remove/replace

Anagrams/Derangements/shuffling

Find/Search/Determine

Formatting

Song lyrics/poems/Mad Libs/phrases

Tokenize

Sequences

11l

<lang 11l>V extra = ‘little’ print(‘Mary had a ’extra‘ lamb.’) print(‘Mary had a #. lamb.’.format(extra)) print(f:‘Mary had a {extra} lamb.’)</lang>

Output:

Mary had a little lamb.
Mary had a little lamb.
Mary had a little lamb.

AArch64 Assembly

Works with: as version Raspberry Pi 3B version Buster 64 bits

<lang AArch64 Assembly> /* ARM assembly AARCH64 Raspberry PI 3B */ /* program insertString64.s */ /* In assembler, there is no function to insert a chain */ /* so this program offers two functions to insert */ /*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly*/ .include "../includeConstantesARM64.inc"

.equ CHARPOS, '@'

/*******************************************/ /* Initialized data */ /*******************************************/ .data szString: .asciz " string " szString1: .asciz "insert" szString2: .asciz "abcd@efg" szString3: .asciz "abcdef @" szString4: .asciz "@ abcdef" szCarriageReturn: .asciz "\n" /*******************************************/ /* UnInitialized data */ /*******************************************/ .bss /*******************************************/ /* code section */ /*******************************************/ .text .global main main: // entry of program

   ldr x0,qAdrszString          // string address
   ldr x1,qAdrszString1         // string address
   mov x2,#0
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

   ldr x0,qAdrszString          // string address
   ldr x1,qAdrszString1         // string address
   mov x2,#3
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

   ldr x0,qAdrszString          // string address
   ldr x1,qAdrszString1         // string address
   mov x2,#40
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

   ldr x0,qAdrszString2         // string address
   ldr x1,qAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

   ldr x0,qAdrszString3         // string address
   ldr x1,qAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

   ldr x0,qAdrszString4         // string address
   ldr x1,qAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr x0,qAdrszCarriageReturn
   bl affichageMess

100: // standard end of the program

   mov x0, #0                   // return code
   mov x8, #EXIT                // request to exit program
   svc 0                        // perform the system call

qAdrszString: .quad szString qAdrszString1: .quad szString1 qAdrszString2: .quad szString2 qAdrszString3: .quad szString3 qAdrszString4: .quad szString4 qAdrszCarriageReturn: .quad szCarriageReturn /******************************************************************/ /* insertion of a sub-chain in a chain in the desired position */ /******************************************************************/ /* x0 contains the address of string 1 */ /* x1 contains the address of string to insert */ /* x2 contains the position of insertion :

     0 start string 
     if x2 > lenght string 1 insert at end of string*/

/* x0 return the address of new string on the heap */ strInsert:

   stp x1,lr,[sp,-16]!                      // save  registers
   stp x2,x3,[sp,-16]!                      // save  registers
   mov x3,#0                                // length counter

1: // compute length of string 1

   ldrb w4,[x0,x3]
   cmp w4,#0
   cinc  x3,x3,ne                           // increment to one if not equal
   bne 1b                                   // loop if not equal
   mov x5,#0                                // length counter insertion string

2: // compute length of insertion string

   ldrb w4,[x1,x5]
   cmp x4,#0
   cinc  x5,x5,ne                           // increment to one if not equal
   bne 2b
   cmp x5,#0
   beq 99f                                  // string empty -> error
   add x3,x3,x5                             // add 2 length
   add x3,x3,#1                             // +1 for final zero
   mov x6,x0                                // save address string 1
   mov x0,#0                                // allocation place heap
   mov x8,BRK                               // call system 'brk'
   svc #0
   mov x5,x0                                // save address heap for output string
   add x0,x0,x3                             // reservation place x3 length
   mov x8,BRK                               // call system 'brk'
   svc #0
   cmp x0,#-1                               // allocation error
   beq 99f
   //
   mov x8,#0                                // index load characters string 1
   cmp x2,#0                                // index insertion = 0
   beq 5f                                   // insertion at string 1 begin

3: // loop copy characters string 1

   ldrb w0,[x6,x8]                          // load character
   cmp w0,#0                                // end string ?
   beq 5f                                   // insertion at end
   strb w0,[x5,x8]                          // store character in output string
   add x8,x8,#1                             // increment index
   cmp x8,x2                                // < insertion index ?
   blt 3b                                   // yes -> loop

5:

   mov x4,x8                                // init index character output string
   mov x3,#0                                // index load characters insertion string

6:

   ldrb w0,[x1,x3]                          // load characters insertion string
   cmp w0,#0                                // end string ?
   beq 7f
   strb w0,[x5,x4]                          // store in output string
   add x3,x3,#1                             // increment index
   add x4,x4,#1                             // increment output index
   b 6b                                     // and loop

7:

   ldrb w0,[x6,x8]                          // load other character string 1
   strb w0,[x5,x4]                          // store in output string
   cmp x0,#0                                // end string 1 ?
   beq 8f                                   // yes -> end
   add x4,x4,#1                             // increment output index
   add x8,x8,#1                             // increment index
   b 7b                                     // and loop

8:

   mov x0,x5                                // return output string address 
   b 100f

99: // error

   mov x0,#-1

100:

   ldp x2,x3,[sp],16                        // restaur  2 registers
   ldp x1,lr,[sp],16                        // restaur  2 registers
   ret

/******************************************************************/ /* insert string at character insertion */ /******************************************************************/ /* x0 contains the address of string 1 */ /* x1 contains the address of insertion string */ /* x0 return the address of new string on the heap */ /* or -1 if error */ strInsertAtChar:

   stp x1,lr,[sp,-16]!                      // save  registers
   stp x2,x3,[sp,-16]!                      // save  registers
   mov x3,#0                                // length counter

1: // compute length of string 1

   ldrb w4,[x0,x3]
   cmp w4,#0
   cinc  x3,x3,ne                           // increment to one if not equal
   bne 1b                                   // loop if not equal
   mov x5,#0                                // length counter insertion string

2: // compute length to insertion string

   ldrb w4,[x1,x5]
   cmp x4,#0
   cinc  x5,x5,ne                           // increment to one if not equal
   bne 2b                                   // and loop
   cmp x5,#0
   beq 99f                                  // string empty -> error
   add x3,x3,x5                             // add 2 length
   add x3,x3,#1                             // +1 for final zero
   mov x6,x0                                // save address string 1
   mov x0,#0                                // allocation place heap
   mov x8,BRK                               // call system 'brk' 
   svc #0
   mov x5,x0                                // save address heap for output string
   add x0,x0,x3                             // reservation place x3 length
   mov x8,BRK                               // call system 'brk'
   svc #0
   cmp x0,#-1                               // allocation error
   beq 99f
   
   mov x2,0
   mov x4,0

3: // loop copy string begin

   ldrb w3,[x6,x2]
   cmp w3,0
   beq 99f
   cmp w3,CHARPOS                           // insertion character ?
   beq 5f                                   // yes
   strb w3,[x5,x4]                          // no store character in output string
   add x2,x2,1
   add x4,x4,1
   b 3b                                     // and loop

5: // x4 contains position insertion

   add x8,x4,1                              // init index character output string
                                            // at position insertion + one
   mov x3,#0                                // index load characters insertion string

6:

   ldrb w0,[x1,x3]                          // load characters insertion string
   cmp w0,#0                                // end string ?
   beq 7f                                   // yes 
   strb w0,[x5,x4]                          // store in output string
   add x3,x3,#1                             // increment index
   add x4,x4,#1                             // increment output index
   b 6b                                     // and loop

7: // loop copy end string

   ldrb w0,[x6,x8]                          // load other character string 1
   strb w0,[x5,x4]                          // store in output string
   cmp x0,#0                                // end string 1 ?
   beq 8f                                   // yes -> end
   add x4,x4,#1                             // increment output index
   add x8,x8,#1                             // increment index
   b 7b                                     // and loop

8:

   mov x0,x5                                // return output string address 
   b 100f

99: // error

   mov x0,#-1

100:

   ldp x2,x3,[sp],16                        // restaur  2 registers
   ldp x1,lr,[sp],16                        // restaur  2 registers
   ret

/********************************************************/ /* File Include fonctions */ /********************************************************/ /* for this file see task include a file in language AArch64 assembly */ .include "../includeARM64.inc" </lang>

Action!

<lang Action!>PROC Main()

 CHAR ARRAY extra="little"

 PrintF("Mary had a %S lamb.%E",extra)

RETURN</lang>

Output:

Screenshot from Atari 8-bit computer

Mary had a little lamb.

Ada

<lang Ada>with Ada.Strings.Fixed, Ada.Text_IO; use Ada.Strings, Ada.Text_IO; procedure String_Replace is

  Original : constant String := "Mary had a @__@ lamb.";
  Tbr : constant String := "@__@";
  New_Str : constant String := "little";
  Index : Natural := Fixed.Index (Original, Tbr);

begin

  Put_Line (Fixed.Replace_Slice (
    Original, Index, Index + Tbr'Length - 1, New_Str));

end String_Replace;</lang>

Alternatively

Aikido

<lang aikido>const little = "little" printf ("Mary had a %s lamb\n", little)

// alternatively println ("Mary had a " + little + " lamb")</lang>

ALGOL 68

Translation of: C

Works with: ALGOL 68 version Revision 1 - no extensions to language used

Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny

strings are simply flex arrays of char. formats on the other hand take on some of the properties of procedures including the scoping rules. <lang algol68>main:(

as a STRING #

 STRING extra = "little";
 printf(($"Mary had a "g" lamb."l$, extra));

as a FORMAT #

 FORMAT extraf = $"little"$;
 printf($"Mary had a "f(extraf)" lamb."l$);

or: use simply use STRING concatenation #

 print(("Mary had a "+extra+" lamb.", new line))

)</lang>

Output:

Mary had a little lamb.
Mary had a little lamb.
Mary had a little lamb.

ARM Assembly

Works with: as version Raspberry Pi

<lang ARM Assembly> /* ARM assembly Raspberry PI */ /* program insertString.s */

/* REMARK 1 : this program use routines in a include file

  see task Include a file language arm assembly 
  for the routine affichageMess conversion10 
  see at end of this program the instruction include */

/*******************************************/ /* Constantes */ /*******************************************/ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall .equ BRK, 0x2d @ Linux syscall .equ CHARPOS, '@'

/*******************************************/ /* Initialized data */ /*******************************************/ .data szString: .asciz " string " szString1: .asciz "insert" szString2: .asciz "abcd@efg" szString3: .asciz "abcdef @" szString4: .asciz "@ abcdef" szCarriageReturn: .asciz "\n" /*******************************************/ /* UnInitialized data */ /*******************************************/ .bss /*******************************************/ /* code section */ /*******************************************/ .text .global main main: // entry of program

   ldr r0,iAdrszString          // string address
   ldr r1,iAdrszString1         // string address
   mov r2,#0
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

   ldr r0,iAdrszString          // string address
   ldr r1,iAdrszString1         // string address
   mov r2,#3
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

   ldr r0,iAdrszString          // string address
   ldr r1,iAdrszString1         // string address
   mov r2,#40
   bl strInsert                 // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

   ldr r0,iAdrszString2         // string address
   ldr r1,iAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

   ldr r0,iAdrszString3         // string address
   ldr r1,iAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

   ldr r0,iAdrszString4         // string address
   ldr r1,iAdrszString1         // string address
   bl strInsertAtChar           // 
                                // return new pointer
   bl affichageMess             // display result string
   ldr r0,iAdrszCarriageReturn
   bl affichageMess

100: // standard end of the program

   mov r0, #0                   // return code
   mov r7, #EXIT                // request to exit program
   svc 0                        // perform the system call

iAdrszString: .int szString iAdrszString1: .int szString1 iAdrszString2: .int szString2 iAdrszString3: .int szString3 iAdrszString4: .int szString4 iAdrszCarriageReturn: .int szCarriageReturn /******************************************************************/ /* insertion of a sub-chain in a chain in the desired position */ /******************************************************************/ /* r0 contains the address of string 1 */ /* r1 contains the address of string to insert */ /* r2 contains the position of insertion :

     0 start string 
     if r2 > lenght string 1 insert at end of string*/

/* r0 return the address of new string on the heap */ strInsert:

   push {r1-r4,lr}                         @ save  registres
   mov r3,#0                                // length counter

1: // compute length of string 1

   ldrb r4,[r0,r3]
   cmp r4,#0
   addne r3,r3,#1                          // increment to one if not equal
   bne 1b                                   // loop if not equal
   mov r5,#0                                // length counter insertion string

2: // compute length of insertion string

   ldrb r4,[r1,r5]
   cmp r4,#0
   addne r5,r5,#1                          // increment to one if not equal
   bne 2b
   cmp r5,#0
   beq 99f                                  // string empty -> error
   add r3,r3,r5                             // add 2 length
   add r3,r3,#1                             // +1 for final zero
   mov r6,r0                                // save address string 1
   mov r0,#0                                // allocation place heap
   mov r7,#BRK                               // call system 'brk'
   svc #0
   mov r5,r0                                // save address heap for output string
   add r0,r0,r3                             // reservation place r3 length
   mov r7,#BRK                               // call system 'brk'
   svc #0
   cmp r0,#-1                               // allocation error
   beq 99f
   //
   mov r7,#0                                // index load characters string 1
   cmp r2,#0                                // index insertion = 0
   beq 5f                                   // insertion at string 1 begin

3: // loop copy characters string 1

   ldrb r0,[r6,r7]                          // load character
   cmp r0,#0                                // end string ?
   beq 5f                                   // insertion at end
   strb r0,[r5,r7]                          // store character in output string
   add r7,r7,#1                             // increment index
   cmp r7,r2                                // < insertion index ?
   blt 3b                                   // yes -> loop

5:

   mov r4,r7                                // init index character output string
   mov r3,#0                                // index load characters insertion string

6:

   ldrb r0,[r1,r3]                          // load characters insertion string
   cmp r0,#0                                // end string ?
   beq 7f
   strb r0,[r5,r4]                          // store in output string
   add r3,r3,#1                             // increment index
   add r4,r4,#1                             // increment output index
   b 6b                                     // and loop

7:

   ldrb r0,[r6,r7]                          // load other character string 1
   strb r0,[r5,r4]                          // store in output string
   cmp r0,#0                                // end string 1 ?
   beq 8f                                   // yes -> end
   add r4,r4,#1                             // increment output index
   add r7,r7,#1                             // increment index
   b 7b                                     // and loop

8:

   mov r0,r5                                // return output string address 
   b 100f

99: // error

   mov r0,#-1

100:

   pop {r1-r4,lr}                          @ restaur registers 
   bx lr                                   @ return

/******************************************************************/ /* insert string at character insertion */ /******************************************************************/ /* r0 contains the address of string 1 */ /* r1 contains the address of insertion string */ /* r0 return the address of new string on the heap */ /* or -1 if error */ strInsertAtChar:

   push {r1-r7,lr}                         @ save  registres
   mov r3,#0                                // length counter

1: // compute length of string 1

   ldrb r4,[r0,r3]
   cmp r4,#0
   addne r3,r3,#1                           // increment to one if not equal
   bne 1b                                   // loop if not equal
   mov r5,#0                                // length counter insertion string

2: // compute length to insertion string

   ldrb r4,[r1,r5]
   cmp r4,#0
   addne r5,r5,#1                           // increment to one if not equal
   bne 2b                                   // and loop
   cmp r5,#0
   beq 99f                                  // string empty -> error
   add r3,r3,r5                             // add 2 length
   add r3,r3,#1                             // +1 for final zero
   mov r6,r0                                // save address string 1
   mov r0,#0                                // allocation place heap
   mov r7,#BRK                               // call system 'brk' 
   svc #0
   mov r5,r0                                // save address heap for output string
   add r0,r0,r3                             // reservation place r3 length
   mov r7,#BRK                               // call system 'brk'
   svc #0
   cmp r0,#-1                               // allocation error
   beq 99f

   mov r2,#0
   mov r4,#0

3: // loop copy string begin

   ldrb r3,[r6,r2]
   cmp r3,#0
   beq 99f
   cmp r3,#CHARPOS                           // insertion character ?
   beq 5f                                   // yes
   strb r3,[r5,r4]                          // no store character in output string
   add r2,r2,#1
   add r4,r4,#1
   b 3b                                     // and loop

5: // r4 contains position insertion

   add r7,r4,#1                              // init index character output string
                                            // at position insertion + one
   mov r3,#0                                // index load characters insertion string

6:

   ldrb r0,[r1,r3]                          // load characters insertion string
   cmp r0,#0                                // end string ?
   beq 7f                                   // yes 
   strb r0,[r5,r4]                          // store in output string
   add r3,r3,#1                             // increment index
   add r4,r4,#1                             // increment output index
   b 6b                                     // and loop

7: // loop copy end string

   ldrb r0,[r6,r7]                          // load other character string 1
   strb r0,[r5,r4]                          // store in output string
   cmp r0,#0                                // end string 1 ?
   beq 8f                                   // yes -> end
   add r4,r4,#1                             // increment output index
   add r7,r7,#1                             // increment index
   b 7b                                     // and loop

8:

   mov r0,r5                                // return output string address 
   b 100f

99: // error

   mov r0,#-1

100:

   pop {r1-r7,lr}                          @ restaur registers 
   bx lr                                   @ return

/***************************************************/ /* ROUTINES INCLUDE */ /***************************************************/ .include "../affichage.inc" </lang>

Output:

insert string
 stinsertring
 string insert
abcdinsertefg
abcdef insert
insert abcdef

APL

     s ← 'Mary had a ∆ lamb' ⋄ s[s⍳'∆'] ← ⊂'little' ⋄ s ← ∊s
     s

Mary had a little lamb

⍝⍝⍝ Or, for a more general version which interpolates multiple positional arguments and can ⍝⍝⍝ handle both string and numeric types...

∇r ← s sInterp sv ⍝⍝ Interpolate items in sv into s (string field substitution) ⍝ s: string - format string, '∆' used for interpolation points ⍝ sv: vector - vector of items to interpolate into s ⍝ r: interpolated string

 s[('∆'=s)/⍳⍴s] ← ⊃¨(⍕¨sv)
 r ← ∊s

∇

     'Mary had a ∆ lamb, its fleece was ∆ as ∆.' sInterp 'little' 'black' 'night'

Mary had a little lamb, its fleece was black as night.

     'Mary had a ∆ lamb, its fleece was ∆ as ∆.' sInterp 'little' 'large' 42

Mary had a little lamb, its fleece was large as 42. </lang>

Arturo

<lang rebol>sizeOfLamb: "little"

print ~"Mary had a |sizeOfLamb| lamb."</lang>

Output:

Mary had a little lamb.

Asymptote

<lang Asymptote>string s1 = "big"; write("Mary had a " + s1 + " lamb"); s1 = "little"; write("Mary also had a ", s1, "lamb");</lang>

AutoHotkey

<lang AutoHotkey>; Using the = operator LIT = little string = Mary had a %LIT% lamb.

Using the: = operator

LIT := "little" string := "Mary had a" LIT " lamb."

MsgBox %string%</lang>

Documentation: Variables (see Storing values in variables and Retrieving the contents of variables)

AWK

String interpolation is usually done with functions sub() and gsub(). gawk has also gensub(). <lang AWK>#!/usr/bin/awk -f BEGIN { str="Mary had a # lamb." gsub(/#/, "little", str) print str }</lang>

BASIC

BASIC256

<lang basic256>x$ = "big" print "Mary had a "; x$; " lamb"

x$ = "little" print "Mary also had a "; ljust(x$, length(x$)); " lamb"</lang>

QBasic

<lang QBasic>x$ = "big" PRINT "Mary had a "; x$; " lamb" x$ = "little" PRINT USING "Mary also had a & lamb"; x$ ' this code above doesn't modify the first string subsustituting a piece of it with another string 'surely it gives the right output on the screen</lang>

True BASIC

<lang qbasic>LET x$ = "big" PRINT "Mary had a "; x$; " lamb"

LET x$ = "little" PRINT USING "Mary had another $##### lamb": x$

LET outstring$ = USING$("$#####", x$) PRINT "Mary also had a "; outstring$; " lamb" END</lang>

Yabasic

<lang yabasic>x$ = "big" print "Mary had a ", x$, " lamb"</lang>

Batch File

<lang dos>@echo off setlocal enabledelayedexpansion call :interpolate %1 %2 res echo %res% goto :eof

interpolate

set pat=%~1 set str=%~2 set %3=!pat:X=%str%! goto :eof</lang>

Demo <lang dos>>interpolate.cmd "Mary had a X lamb" little Mary had a little lamb</lang>

BQN

_interpolate is a generalized string interpolation modifier that returns a function based on the replacement character given. The function will take a string on the right and replace the given symbol with the elements of the array given on its left.

Here, the symbol for Nothing(`·`) is used as a replacement character.

<lang bqn>Str ← (3⌊•Type)◶⟨2=•Type∘⊑,0,1,0⟩ _interpolate ← {∾(•Fmt⍟(¬Str)¨𝕨)⌾((𝕗=𝕩)⊸/)𝕩}

'a'‿"def"‿45‿⟨1,2,3⟩‿0.34241 '·'_interpolate "Hi · am · and · or · float ·"</lang>

Bracmat

Use pattern matching to find the part of the string up to and the part of the string following the magic X. Concatenate these parts with the string "little" in the middle.

<lang bracmat>@("Mary had a X lamb":?a X ?z) & str$(!a little !z)</lang>

C

Include the <stdio.h> header to use the functions of the printf family: <lang c>#include <stdio.h>

int main() {

 const char *extra = "little";
 printf("Mary had a %s lamb.\n", extra);
 return 0;

}</lang>

C#

This is called "composite formatting" in MSDN.

<lang csharp>class Program {

   static void Main()
   {
       string extra = "little";
       string formatted = $"Mary had a {extra} lamb.";
       System.Console.WriteLine(formatted);
   }

}</lang>

C++

<lang cpp>#include <string>

include <iostream>

int main( ) {

  std::string original( "Mary had a X lamb." ) , toBeReplaced( "X" ) ,
     replacement ( "little" ) ;
  std::string newString = original.replace( original.find( "X" ) ,

toBeReplaced.length( ) , replacement ) ;

  std::cout << "String after replacement: " << newString << " \n" ;
  return 0 ;

}</lang> ==C++==

Works with: C++11

<lang cpp>// Variable argument template

include <string>
include <vector>

using std::string; using std::vector;

template<typename S, typename... Args> string interpolate( const S& orig , const Args&... args) {

  string out(orig);

  // populate vector from argument list
  auto va = {args...};
  vector<string> v{va};
  
  size_t i = 1;

  for( string s: v)
    {
      string is = std::to_string(i);
      string t = "{" +  is + "}";  // "{1}", "{2}", ...
      try

{ auto pos = out.find(t);

if ( pos != out.npos) // found token { out.erase(pos, t.length()); //erase token out.insert( pos, s); // insert arg }

i++; // next } catch( std::exception& e) { std::cerr << e.what() << std::endl; }

    } // for

  return out;

}</lang>

Clojure

<lang lisp>(let [little "little"]

 (println (format "Mary had a %s lamb." little)))</lang>

COBOL

Works with: OpenCOBOL

<lang cobol> IDENTIFICATION DIVISION.

      PROGRAM-ID. interpolation-included.

      DATA DIVISION.
      WORKING-STORAGE SECTION.
      01  extra PIC X(6) VALUE "little".

      PROCEDURE DIVISION.
          DISPLAY FUNCTION SUBSTITUTE("Mary had a X lamb.", "X", extra)

          GOBACK
          .</lang>

Coco

As CoffeeScript, but the braces are optional if the expression to be interpolated is just a variable:

<lang coco>size = 'little' console.log "Mary had a #size lamb."</lang>

CoffeeScript

<lang coffeescript> size = 'little' console.log "Mary had a #{size} lamb." # Mary had a little lamb. console.log "Escaping: \#{}" # Escaping: #{} console.log 'No #{ interpolation} with single quotes' # No #{ interpolation} with single quotes

Multi-line strings and arbtrary expressions work: 20

console.log """

 Multi-line strings and arbtrary expressions work: #{ 5 * 4 }
 """

</lang>

Common Lisp

<lang lisp>(let ((extra "little"))

 (format t "Mary had a ~A lamb.~%" extra))</lang>

More documentation on the FORMAT function.

D

<lang d>void main() {

   import std.stdio, std.string;

   "Mary had a %s lamb.".format("little").writeln;
   "Mary had a %2$s %1$s lamb.".format("little", "white").writeln;

}</lang>

Output:

Mary had a little lamb.
Mary had a white little lamb.

More documentation on the format() function.

Delphi

<lang Delphi>program Project1;

uses

 System.SysUtils;

var

 Template : string;
 Marker : string;
 Description : string;
 Value : integer;
 Output : string;

begin

 // StringReplace can be used if you are definitely using strings
 // http://docwiki.embarcadero.com/Libraries/XE7/en/System.SysUtils.StringReplace
 Template := 'Mary had a X lamb.';
 Marker := 'X';
 Description := 'little';
 Output := StringReplace(Template, Marker, Description, [rfReplaceAll, rfIgnoreCase]);
 writeln(Output);

 // You could also use format to do the same thing.
 // http://docwiki.embarcadero.com/Libraries/XE7/en/System.SysUtils.Format
 Template := 'Mary had a %s lamb.';
 Description := 'little';
 Output := format(Template,[Description]);
 writeln(Output);

 // Unlike StringReplace, format is not restricted to strings.
 Template := 'Mary had a %s lamb. It was worth $%d.';
 Description := 'little';
 Value := 20;
 Output := format(Template,[Description, Value]);
 writeln(Output);

end.</lang>

Output:

Mary had a little lamb.
Mary had a little lamb.
Mary had a little lamb. It was worth $20.

DWScript

<lang delphi>PrintLn(Format('Mary had a %s lamb.', ['little']))</lang>

Output:

Mary had a little lamb.

Dyalect

Dyalect has a built-in string interpolation feature.

<lang Dyalect>let lamb_size = "little" print("Mary had a \(lamb_size) lamb.")</lang>

E

<lang e>def adjective := "little" `Mary had a $adjective lamb`</lang>

The `...` syntax in general may be used as a sort of syntax extension; string interpolation is just the default case. More information on E quasi-literals. (Note that this documentation may be somewhat out of date.)

The above code is equivalent to (expands into):

<lang e>def adjective := "little" simple__quasiParser.valueMaker("Mary had a ${0} lamb").substitute([adjective])</lang>

If an identifier precedes the opening `, then it replaces simple; the quasiParser may be an arbitrary user-defined object. In this way, E provides lightweight syntax for embedding other languages: XML, JSON, GUI layouts, regular expressions, etc.

EchoLisp

format and printf use replacement directives to perform interpolation. See format specification in EchoLisp documentatiuon. <lang scheme>

format uses %a or ~a as replacement directive

(format "Mary had a ~a lamb" "little")

  → "Mary had a little lamb"

(format "Mary had a %a lamb" "little")

  → "Mary had a little lamb"

</lang>

ECL

<lang ECL> IMPORT STD; STD.Str.FindReplace('Mary had a X Lamb', 'X','little'); </lang>

Elena

ELENA 4.x : <lang elena>import extensions;

public program() {

   var s := "little";
   console.printLineFormatted("Mary had a {0} lamb.",s).readChar()

}</lang>

Elixir

Elixir borrows Ruby's #{...} interpolation syntax. <lang elixir> x = "little" IO.puts "Mary had a #{x} lamb" </lang>

Emacs Lisp

<lang lisp>(let ((little "little"))

 (format "Mary had a %s lamb." little)
 ;; message takes a format string as argument
 (message "Mary had a %s lamb." little))</lang>

Erlang

Output:

7> S1 = "Mary had a ~s lamb".
8> S2 = lists:flatten( io_lib:format(S1, ["big"]) ).
9> S2.
"Mary had a big lamb"

Euphoria

<lang euphoria>constant lambType = "little" sequence s s = sprintf("Mary had a %s lamb.",{lambType}) puts(1,s)</lang> See sprintf, printf

F#

Documentation <lang fsharp>let lambType = "little" printfn "Mary had a %s lamb." lambType</lang>

Factor

<lang factor>USE: formatting

SYMBOL: little

"little" little set

little get "Mary had a %s lamb" sprintf</lang>

I tried to be as specific as possible here. The challenge says to use a variable so that is what I used. It could have been done more cleanly using a CONSTANT.

<lang factor>USE: formatting

CONSTANT: little "little"

little "Mary had a %s lamb" sprintf</lang>

Falcon

'VBA/Python programmer's approach. I'm just a junior Falconeer but this code seems falconic <lang falcon> /* created by Aykayayciti Earl Lamont Montgomery April 9th, 2018 */

size = "little" > @ "Mary had a $size lamb"

// line 1: use of the = operator // line 2: use of the @ and $ operator </lang>

Output:

Mary had a little lamb
[Finished in 0.2s]

Fantom

Interpolating a variable value into a string is done by using a $ prefix on the variable name within a string. For example:

<lang fantom> fansh> x := "little" little fansh> echo ("Mary had a $x lamb") Mary had a little lamb </lang>

Documentation at: Fantom website

Forth

<lang Forth>variable 'src variable #src variable 'out variable #out

Replace~ dup [char] ~ = \ test for escape char

              if   'out @ 1+  #out @ type  drop \ replace the escape char
              else emit                         \ otherwise write  char
              then  ;

format 0

              begin  dup  #src @ u<
              while  1+ dup 'src @ + c@
                     replace~
              repeat ;

\ Test of function Here 'src ! ," Mary had a ~ lamb" here 'src @ - #src ! page cr ." Original : " 'src @ 1+ #src @ type cr ." 1st Replacement : "

 here 'out ! ," little" here 'out @ - #out !
 format

cr ." 2nd Replacement : "

 here 'out  ! ," BIG" here 'out @ - #out !
 format

</lang>

Output:

Original        : Mary had a ~ lamb
1st Replacement : Mary had a little lamb
2nd Replacement : Mary had a BIG lamb

Fortran

<lang Fortran>program interpolate

 write (*,*) trim(inter("Mary had a X lamb.","X","little"))

contains

 elemental function inter(string,place,ins) result(new)
   character(len=*), intent(in)                          :: string,place,ins
   character(len=len(string)+max(0,len(ins)-len(place))) :: new
   integer                                               :: idx
   idx = index(string,place)
   if ( idx == 0 ) then
     new = string
   else
     new = string(1:idx-1)//ins//string(idx+len(place):len(string))
   end if
 end function inter

end program interpolate</lang>

FreeBASIC

FreeBASIC has a complex Print statement which, amongst other things, enables variables to be embedded in the string to be printed.

It is also possible to use C library functions such as printf or sprintf, which allow more conventional string interpolation, as easily as if they were part of FB itself: <lang freebasic>' FB 1.05.0 Win64

Include "crt/stdio.bi" header needed for printf

Dim x As String = "big" Print "Mary had a "; x; " lamb" FB's native Print statement x = "little" printf("Mary also had a %s lamb", x) Sleep</lang>

Output:

Mary had a big lamb
Mary also had a little lamb

Frink

<lang frink>x = "little" println["Mary had a $x lamb."]</lang>

FunL

<lang funl>X = 'little' println( "Mary had a $X lamb." )</lang>

Gambas

Click this link to run this code <lang gambas>Public Sub Main()

Print Subst("Mary had a &1 lamb", "little")

End</lang> Output:

Mary had a little lamb

Gastona

This kind of string interpolation is indeed a strong feature in Gastona. We add one more indirection in the sample just to ilustrate it. <lang gastona>#listix#

  <how>   //little
  <what>  //has a @<how> lamb
  
  <main>  //Mary @<what>

</lang>

Output:

Mary has a little lamb

Go

Doc: http://golang.org/pkg/fmt/ <lang go> package main

import (

   "fmt"

)

func main() {

   str := "Mary had a %s lamb"
   txt := "little"
   out := fmt.Sprintf(str, txt)
   fmt.Println(out)

} </lang>

Groovy

<lang groovy>def adj = 'little' assert 'Mary had a little lamb.' == "Mary had a ${adj} lamb."</lang>

Haskell

No such facilities are defined in Haskell 98, but the base package distributed with GHC provides a printf function.

<lang haskell>import Text.Printf

main = printf "Mary had a %s lamb\n" "little"</lang>

Haxe

Translation of: C#

<lang haxe>class Program {

 static function main() {
   var extra = 'little';
   var formatted = 'Mary had a $extra lamb.';
   Sys.println(formatted);
 }

}</lang>

Output:

Mary had a little lamb.

HicEst

Further documentation on HicEst string interpolation function EDIT() <lang hicest>CHARACTER original="Mary had a X lamb", little = "little", output_string*100

output_string = original EDIT(Text=output_string, Right='X', RePLaceby=little)</lang>

Icon and Unicon

Icon and Unicon are descended from a line of languages with a wealth of string manipulation capabilities. See The Icon Programming Language, 3rd Edition; Griswold and Griswold; Chapter 3 String Scanning <lang Icon> s2 := "humongous"

 s3 := "little"
 s1 :=  "Mary had a humongous lamb."
 s1 ?:= tab(find(s2)) || (=s2,s3) || tab(0)          # replaces the first instance of s2 with s3
 while s1 ?:= tab(find(s2)) || (=s2,s3) || tab(0)    # replaces all instances of s2 with s3, equivalent to replace</lang>

Library: Icon Programming Library

Note the strings library includes convenient procedures for string replacement such as replace(s1,s2,s3) which replaces all occurrences of s2 in s1 with s3 and replacem(s1,s2,s3,...) which replaces multiple pairs.

J

The strings and printf scripts are part of the base library. <lang j> require 'printf'

  'Mary had a %s lamb.' sprintf <'little'

Mary had a little lamb.

  require 'strings'
  ('%s';'little') stringreplace 'Mary had a %s lamb.'

Mary had a little lamb.

  'Mary had a %s lamb.' rplc '%s';'little'

Mary had a little lamb.</lang>

Documentation:

The comments in these library files give brief descriptions of their contents, and you can browse them using open:

<lang J> open'strings printf'</lang>

Alternatively, both strings and printf have various web pages describing them, and printf has a lab demonstrating its use (from J's IDE's menu, go Studio -> Labs... and then look in the System category).

That said, note that in recent versions of J, strings is no longer a separate script but part of the core library.

Java

<lang java>String original = "Mary had a X lamb"; String little = "little"; String replaced = original.replace("X", little); //does not change the original String System.out.println(replaced); //Alternative: System.out.printf("Mary had a %s lamb.", little); //Alternative: String formatted = String.format("Mary had a %s lamb.", little); System.out.println(formatted);</lang>

JavaScript

<lang javascript>var original = "Mary had a X lamb"; var little = "little"; var replaced = original.replace("X", little); //does not change the original string</lang>

Or,

<lang javascript>// ECMAScript 6 var X = "little"; var replaced = `Mary had a ${X} lamb`;</lang>

jq

<lang jq>"little" as $x

 | "Mary had a \($x) lamb"</lang>

Any valid jq expression (including a pipeline) can appear between the interpolating parentheses, e.g.:<lang jq>$ jq -M -n -r '"Jürgen" as $x | "The string \"\($x)\" has \($x|length) codepoints."' The string "Jürgen" has 6 codepoints.</lang> Documentation: String interpolation

Julia

<lang julia>X = "little" "Mary had a $X lamb"</lang>

Kotlin

<lang scala>// version 1.0.6

fun main(args: Array<String>) {

  val s = "little"
   // String interpolation using a simple variable
   println("Mary had a $s lamb")

   // String interpolation using an expression (need to wrap it in braces)
   println("Mary had a ${s.toUpperCase()} lamb")

   // However if a simple variable is immediately followed by a letter, digit or underscore
   // it must be treated as an expression
   println("Mary had a ${s}r lamb") // not $sr

}</lang>

Output:

Mary had a little lamb
Mary had a LITTLE lamb
Mary had a littler lamb

Lambdatalk

<lang Scheme> {def original Mary had a X lamb} -> original {def Y little} -> Y {S.replace X by {Y} in {original}} -> Mary had a little lamb </lang>

Lasso

Lasso doesn't really have built-in string interpolation, but you can use the built-in email mail-merge capability: <lang lasso>email_merge("Mary had a #adjective# lamb", map("token"="little", "adjective"=""), null, 'plain')</lang>

Output:

Mary had a little lamb

LiveCode

Livecode has a merge function for interpolation <lang LiveCode>local str="little" put merge("Mary had a str lamb.")

-- Mary had a little lamb.</lang>

Lua

Variable names

There is no default support for automatic interpolation of variables names being used as placeholders within a string. However, interpolation is easily emulated by using the [string.gsub] function:

<lang Lua>str = string.gsub( "Mary had a X lamb.", "X", "little" ) print( str )</lang>

or using [string.format] function like C:

<lang lua>str1 = string.format( "Mary had a %s lamb.", "little" ) str2 = ( "Mary had a %s lamb." ):format( "little" ) print( str1, str2 )</lang>

Literal characters

Interpolation of literal characters escape sequences does occur within a string:

<lang lua>print "Mary had a \n lamb" -- The \n is interpreted as an escape sequence for a newline</lang>

M2000 Interpreter

<lang M2000 Interpreter> module checkit {

     size$="little"
     m$=format$("Mary had a {0} lamb.", size$)
     Print m$
     Const RightJustify=1
     \\ format$(string_expression)  process escape codes
     Report RightJustify, format$(format$("Mary had a {0} {1} lamb.\r\n We use {0} for size, and {1} for color\r\n", size$, "wh"+"ite"))
     \\ we can use { } for multi line string
     Report RightJustify, format$({Mary had a {0} {1} lamb.
            We use {0} for size, and {1} for color
            }, size$, "wh"+"ite")

} checkit </lang>

Mathematica/Wolfram Language

<lang Mathematica>Extra = "little"; StringReplace["Mary had a X lamb.", {"X" -> Extra}] ->"Mary had a little lamb."</lang>

Maxima

<lang maxima>printf(true, "Mary had a ~a lamb", "little");</lang>

Neko

<lang actionscript>/**

<doc>

String interpolation, in Neko

<a href="https://nekovm.org/doc/view/string/">NekoVM String Library</a>

</doc>

- /

var sprintf = $loader.loadprim("std@sprintf", 2)

$print(sprintf("Mary had a %s lamb\n", "little"))</lang>

Output:

prompt$ nekoc string-interpolation.neko
prompt$ neko string-interpolation.n
Mary had a little lamb

Nemerle

Nemerle has a few ways to accomplish this. It provides an implementation of printf(), $ interpolation within the print() method, and the most general use is $ interpolation within $ quoted strings. <lang Nemerle>using System; using System.Console; using Nemerle.IO; // contains printf() and print()

module Stringy {

   Main() : void
   {
       def extra = "little";
       printf("Mary had a %s lamb.\n", extra);
       print("Mary had a $extra lamb.\n");
       WriteLine($"Mary had a $extra lamb.");
   }

}</lang>

NetRexx

The Built In Functions (BIFs) of NetRexx can be employed to manipulate strings quite successfully but for more flexible string interpolation a function package like Java's MessageFormat should be used. <lang NetRexx>/* NetRexx */

options replace format comments java crossref savelog symbols

import java.text.MessageFormat import java.text.FieldPosition

useBif() useMessageFormat()

return

method useBif public static

 st = "Mary had a %1$ lamb."
 si = 'little'

 say st.changestr('%1$', si)

 return

method useMessageFormat public static

 result = StringBuffer()

 args = Object [                       -
   Object Integer(7),                  -
   Object Date(),                      -
   Object 'a disturbance in the Force' -
 ]
 msgfmt = MessageFormat('At {1, time} on {1, date}, there was {2} on planet {0, number, integer}.')
 result = msgfmt.format(args, result, FieldPosition(0))
 say result

 return

</lang>

Output:

Mary had a little lamb.
At 5:43:05 PM on Aug 22, 2011, there was a disturbance in the Force on planet 7.

Nim

Nim offers two methods to build a string with interpolation. The first one uses the procedure format or the operator %. Note that with the procedure, an implicit conversion of the arguments is done. With the operator, the conversion must be explicit, using for instance the $ operator. <lang nim>import strutils

var str = "little" echo "Mary had a $# lamb".format(str) echo "Mary had a $# lamb" % [str]

Note: doesn't need an array for a single substitution, but uses an array for multiple substitutions.</lang>

The second method allows to place the expressions directly in the string. There is also two forms, one using the prefix "fmt", the other using the prefix "&". The second form must be used if the string contains newline characters.

<lang nim>import strformat

var str: string = "little" echo fmt"Mary had a {str} lamb" echo &"Mary had a {str} lamb"</lang>

OCaml

The OCaml standard library provides the module Printf:

<lang ocaml>let extra = "little" in Printf.printf "Mary had a %s lamb." extra</lang>

Another option is to use compiler plugin mechanism and ppx_string_interpolation:

<lang ocaml> let extra = "little" in [%string "Mary had a $extra lamb."] </lang>

OOC

In a String all expressions between #{...} will be evaluated. <lang ooc> main: func {

 X := "little"
 "Mary had a #{X} lamb" println()

} </lang>

Oz

String interpolation is unidiomatic in Oz. Instead, "virtual strings" are used. Virtual strings are tuples of printable values and are supported by many library functions.

<lang oz>declare

 X = "little"

in

 {System.showInfo "Mary had a "#X#" lamb"}</lang>

PARI/GP

The Pari library has string interpolation, which extends C's: <lang C>GEN string_interpolate(GEN n) {

 pari_printf("The value was: %Ps.\n", n);
 GEN s = pari_sprintf("Storing %Ps in a string", n);

}</lang>

Works with: PARI/GP version version 2.4.4 and above

GP can also interpolate strings: <lang parigp>s=Strprintf("The value was: %Ps", 1<<20); printf("The value was: %Ps", 1<<20);</lang>

Perl

<lang perl>$extra = "little"; print "Mary had a $extra lamb.\n"; printf "Mary had a %s lamb.\n", $extra;</lang>

Phix

Library: Phix/basics

string size = "little"
string s = sprintf("Mary had a %s lamb.",{size})
?s

Output:

"Mary had a little lamb."

PHP

Picat

 V = "little",
 printf("Mary had a %w lamb\n", V),
 
 % As a function
 S = to_fstring("Mary had a %w lamb", V),
 println(S).</lang>

PicoLisp

<lang PicoLisp>(let Extra "little"

  (prinl (text "Mary had a @1 lamb." Extra)) )</lang>

PL/I

<lang PLI>*process or(!) source xref attributes;

sit: Proc Options(main);
/*********************************************************************
* Test string replacement
* 02.08.2013 Walter Pachl
*********************************************************************/
Dcl s Char(50) Var Init('Mary had a &X lamb. It is &X');
Put Edit(repl(s,'little','&X'))(Skip,A);

repl: Proc(str,new,old) Returns(Char(50) Var);
/*********************************************************************
* ooREXX has CHANGESTR(old,str,new[,count])
* repl follows, however, the translate "philosophy"
* translate(str,new,old) when old and new are just  a character each
* and replaces all occurrences of old in str by new
*********************************************************************/
Dcl str Char(*) Var;
Dcl (new,old) Char(*);
Dcl (res,tmp) Char(50) Var init();
Dcl p Bin Fixed(31);
tmp=str;                             /* copy the input string       */
Do Until(p=0);
  p=index(tmp,old);                  /* position of old in tmp      */
  If p>0 Then Do;                    /* found                       */
    res=res!!left(tmp,p-1)!!new;     /* append new to current result*/
    tmp=substr(tmp,p+length(old));   /* prepare rest of input       */
    End;
  End;
res=res!!tmp;                        /* final append                */
Return(res);
End;
End;</lang>

Output:

Mary had a little lamb. It is little

PowerShell

Using the format (-f) operator: <lang powershell>$extra = "little" "Mary had a {0} lamb." -f $extra</lang>

Using format string with the WriteLine static method <lang powershell>$extra = "little" [console]::writeline("Mary had a {0} lamb.", $extra)</lang>

Using the format method of the string type <lang powershell>$extra = "little" [string]::Format("Mary had a {0} lamb.", $extra)</lang>

Note: numeric and date/time formats can be specified with {index:formatString} (i.e. {0:###,###})

Prolog

<lang Prolog>Extra = little, format('Mary had a ~w lamb.', [Extra]), % display result format(atom(Atom), 'Mary had a ~w lamb.', [Extra]). % ... or store it a variable</lang>

Using library(func) for SWI-Prolog:

<lang Prolog>Extra = little, Atom = 'Mary had a ~w lamb' $ Extra.</lang>

Using library(interpolate) for SWI-Prolog:

<lang Prolog>Extra = little, Atom = 'Mary had a $Extra lamb'.</lang>

PureBasic

The function ReplaceString() is built-in and can have both constants and variables as parameters. <lang PureBasic>ReplaceString("Mary had a X lamb.","X","little")</lang> Implemented in a program context <lang PureBasic>; String variable can be defined by appending .s to its name during definition or by appending and using $ as a part of its name. Define txt$, txtvar.s="little"

Load datasegment into variable txt$

Restore Mary Read.s txt$

Replace X with "little" and store result in txt$

txt$=ReplaceString(txt$,"X",txtvar)

OpenConsole(): Print(txt$)

DataSection:

 Mary:
 Data.s  "Mary had a X lamb."

EndDataSection</lang>

Python

Python has more than one inbuilt way of accomplishing the task. The methods have different capabilities that are not stretched by this small task

Using the % string interpolation operator: <lang python>>>> original = 'Mary had a %s lamb.' >>> extra = 'little' >>> original % extra 'Mary had a little lamb.'</lang>

Using the .format method of strings: <lang python>>>> original = 'Mary had a {extra} lamb.' >>> extra = 'little' >>> original.format(**locals()) 'Mary had a little lamb.'</lang> Using the format method, but replace by an expressions position as an argument to the format method call instead of by name: <lang python>>>> original = 'Mary had a {0} lamb.' >>> extra = 'little' >>> original.format(extra) 'Mary had a little lamb.'</lang>

Using the Template class of the string module: <lang python>>>> from string import Template >>> original = Template('Mary had a $extra lamb.') >>> extra = 'little' >>> original.substitute(**locals()) 'Mary had a little lamb.'</lang>

Using the new f-strings string literal available from Python 3.6: <lang python>>>> extra = 'little' >>> f'Mary had a {extra} lamb.' 'Mary had a little lamb.' >>> </lang>

QB64

<lang QB64> DefStr S

' Qbasic /QuickBasic MID$ statement needs that string2 and substring ' to replace in string1 must have the same length, ' otherwise it overwrites the following part of string1 String1 = "Mary has a X lamb" Print String1, "Original String1" Print "Interpolation of string by MID$ statement" String2 = "little" Mid$(String1, InStr(String1, "X")) = String2 Print String1

String1 = "Mary has a X lamb" String2 = "@" Mid$(String1, InStr(String1, "X")) = String2 Print String1

Print "Interpolation by string's functions" String1 = "Mary has a X lamb" String2 = "little" String1 = Mid$(String1, 1, InStr(String1, "X") - 1) + String2 + Mid$(String1, InStr(String1, "X") + 1, Len(String1) - InStr(String1, "X")) Print String1, "by MID$"

String1 = "Mary has a X lamb" String2 = "#§[]@" String1 = Left$(String1, InStr(String1, "X") - 1) + String2 + Right$(String1, Len(String1) - InStr(String1, "X") + 1) Print String1, "by LEFT$ and RIGHT$"

</lang>

Racket

See the documentation on fprintf for more information on string interpolation in Racket.

lang racket

(format "Mary had a ~a lamb" "little") </lang>

Raku

(formerly Perl 6) <lang perl6>my $extra = "little"; say "Mary had a $extra lamb"; # variable interpolation say "Mary had a { $extra } lamb"; # expression interpolation printf "Mary had a %s lamb.\n", $extra; # standard printf say $extra.fmt("Mary had a %s lamb"); # inside-out printf my @lambs = <Jimmy Bobby Tommy>; say Q :array { $$$ The lambs are called @lambs[]\\\.} # only @-sigiled containers are interpolated</lang>

REBOL

<lang rebol>str: "Mary had a <%size%> lamb" size: "little" build-markup str

REBOL3 also has the REWORD function

str: "Mary had a $size lamb" reword str [size "little"]</lang>

REXX

Interpolation does not occur in literal strings, neither within singlequote or doublequote enclosures.
However, interpolation can be emulated using the changestr function:

<lang rexx>/*REXX program to demonstrate string interpolation (string replacement).*/

                                      /*the string to be replaced is   */

replace = "little" /*usually a unique character(s) */

                                      /*string and is  case  sensative.*/

original1 = "Mary had a X lamb." new1 = changestr('X', original1, replace) say 'original1 =' original1 say 'replaced =' new1 say

original2 = "Mary had a % lamb." new2 = changestr('%', original2, replace) say 'original2 =' original2 say 'replaced =' new2 say

original3 = "Mary had a $$$ lamb." new3 = changestr('$$$',original3,replace) say 'original3 =' original3 say 'replaced3 =' new3 say

original4 = "Mary had a someKindOf lamb." new3 = changestr('someKindOf', original4, "little") say 'original4 =' original4 say 'replaced4 =' new3

                                      /*stick a fork in it, we're done.*/</lang>

Some older REXXes don't have a changestr BIF, so one is included here ──► CHANGESTR.REX.

output

original1 = Mary had a X lamb.
replaced  = Mary had a little lamb.

original2 = Mary had a % lamb.
replaced  = Mary had a little lamb.

original3 = Mary had a $$$ lamb.
replaced3 = Mary had a little lamb.

original4 = Mary had a someKindOf lamb.
replaced4 = Mary had a little lamb.

Ring

<lang ring> aString =substr("Mary had a X lamb.", "X", "little") see aString + nl </lang>

Ruby

<lang ruby>irb(main):001:0> extra = 'little' => "little" irb(main):002:0> "Mary had a #{extra} lamb." => "Mary had a little lamb." irb(main):003:0> "Mary had a %s lamb." % extra => "Mary had a little lamb."</lang>

Documentation:

string_spec.rb describes interpolation using #{....} in double-quoted strings.
Core API describes printf-style interpolation by String#% and Kernel#sprintf.

Run BASIC

<lang runbasic>"a$ = Mary had a X lamb." a$ = word$(a$,1,"X")+"little"+word$(a$,2,"X") print a$ </lang>

Rust

Rust has very powerful string interpolation. Documentation here. <lang rust>fn main() {

   println!("Mary had a {} lamb", "little");
   // You can specify order
   println!("{1} had a {0} lamb", "little", "Mary");
   // Or named arguments if you prefer
   println!("{name} had a {adj} lamb", adj="little", name="Mary");

}</lang>

Scala

Library: Scala

<lang Scala>object StringInterpolation extends App {

 import util.matching.Regex._
 val size = "little"

 { // Method I (preferred)
   // Scala 2.10.0 supports direct string interpolation
   // by putting "s" at the beginning of the string.
   println("V2.10+  : " + s"Mary had a $size lamb,")
 }

 { // Method II
   // Pre Scala 2.10 indirect use of Java Class Formatter
   val originalFormatter = "Mary had a %s lamb,"
   println("V2.10- 1: " + originalFormatter format size)
   // Above mentioned is Scala's postfix notation and equivalent for: 
   println("V2.10- 2: " + originalFormatter.format(size))
   // Also possible
   printf(("V2.10- 3: " + originalFormatter + '\n').format(size))
   // All will be expanded to
   print(("V2.10- 3: " + originalFormatter + '\n').format(size))
   print((new java.util.Formatter).format("V2.10- 4: " + originalFormatter + '\n', size))
 }

 { // Method III
   // Regular expressions, only for demonstration
   val extractor = """\$\{([^}]+)\}""".r
   println((extractor.replaceAllIn("Regex  1: Mary had a ${x} lamb,", "snow white")))

   // RegEx freaking
   def interpolate(text: String, vars: (String, String)*) =
     extractor.replaceAllIn(text,
       _ match { case Groups(v) => vars.toMap.getOrElse(v, "" /*in case nothing provided*/ ) })

   println(interpolate("Regex  2: ${who} had a ${size} ${pet}, ${unknown}",
     ("pet", "lamb"), ("size", "fat"), ("size", "humongous"), ("who", "Mary")))
 }

 { // Method IV, not recommended.
   // Standard API method, search argument (1st ones) supposed to be a regular expression
   println("Replace1: " + "Mary had a ${x} lamb".replaceAll("""\$\{x\}""", size))
   // Standard API method, literally, on regular expression
   println("Replace2: " + "Mary had a ${x} lamb".replaceAllLiterally("${x}", size))
 }

 { // Method IV, not recommended.
   println("Split   : " + "Mary had a ${x} lamb.".split("""\$\{([^}]+)\}""").mkString(size))
 }

}</lang> Documentation:

Scala 2.10.0: string interpolation

Sed

<lang bash>#!/bin/bash

Usage example: . interpolate "Mary has a X lamb" "quite annoying"

echo "$1" | sed "s/ X / $2 /g"</lang>

Seed7

<lang seed7>$ include "seed7_05.s7i";

const proc: main is func

 local
   const string: original is "Mary had a X lamb";
   const string: little is "little";
   var string: replaced is "";
 begin
   replaced := replace(original, "X", little);
   writeln(replaced);
 end func;</lang>

Output:

Mary had a little lamb

SenseTalk

SenseTalk does string interpolation through the merge function, which can evaluate any sort of embedded expression, including entire sections of code like conditionals or repeat loops. For convenience, the merge function can be invoked by simply using a ! before a string literal (this is needed because string literals are actually literal in SenseTalk -- there are no characters with hidden meaning by default). <lang sensetalk>put "little" into x

put "Mary had a x lamb." -- this is a literal string put !"Mary had a x lamb." -- this is an interpolated string put put !"repeat with n=2 to 6Mary had n x lambs.return end repeat" put !"Mary had repeat with n=2 to 6 n x end repeatlambs." </lang>

Output:

Mary had a [[x]] lamb.
Mary had a little lamb.

Mary had 2 little lambs.
Mary had 3 little lambs.
Mary had 4 little lambs.
Mary had 5 little lambs.
Mary had 6 little lambs.

Mary had 2 little 3 little 4 little 5 little 6 little lambs.

Sidef

<lang ruby>var extra = 'little'; say "Mary had a #{extra} lamb";</lang>

or: <lang ruby>say ("Mary had a %s lamb" % 'little');</lang>

See: documentation

SNOBOL4

Every statement in SNOBOL can is a subset of pattern replacement having a subject (s1 in this case), object (s2), and replacement (s3). <lang snobol> s1 = "Mary had a humongous lamb." s2 = "humongous"

       s3 = "little"

s1 s2 = s3 end</lang> See The SNOBOL4 Programming Language; Griswold, Poage, Polonsky; Chapter 2 Pattern Matching

Stata

See printf in Stata help.

<lang stata>: printf("Mary had a %s lamb.\n", "little") Mary had a little lamb.</lang>

Swift

<lang swift>let extra = "little" println("Mary had a \(extra) lamb.")</lang>

Tailspin

String interpolation is the normal way to create strings in Tailspin, see string literal in the Tailspin reference <lang tailspin> def size: 'little'; 'Mary had a $size; lamb' -> !OUT::write </lang>

Tcl

String interpolation is a fundamental operation of the Tcl language itself, and is carried out in a "double-quoted" program strings as well as bare-words. Thus, interpolation of the string from a variable is carried out with the $ syntax and the string result of a command is interpolated with the […] syntax. <lang tcl>set size "little" puts "Mary had a $size lamb."

proc RandomWord {args} {

  lindex $args [expr {int(rand()*[llength $args])}]

} puts "Mary had a [RandomWord little big] lamb."</lang> When more sophisticated control is required the format command can be used, which is very similar to the standard C library's sprintf function: <lang tcl>puts [format "Mary had a %s %s." [RandomWord little big] [RandomWord lamb piglet calf]]</lang>

A third approach is to use string map. <lang tcl>set s "Mary had a @SIZE@ lamb." puts [string map {@SIZE@ "miniscule"} $s]</lang>

Tcl also supports variable variable names. Even more powerful is nested interpolation with the subst command. <lang tcl>set grandpa {$daddy}; set grandma \$mommy set daddy myself; set mommy {lil' bro} set fun1 \[string\ to set fun2 lower set lower middle set middle upper set fun3 {aNd]} puts [subst "$grandpa $fun1$[subst $$fun2] $fun3 $grandma"]</lang>

TUSCRIPT

<lang tuscript> $$ MODE TUSCRIPT

sentence_old="Mary had a X lamb."

values=* DATA little DATA big

sentence_new=SUBSTITUTE (sentence_old,":X:",0,0,values) PRINT sentence_old PRINT sentence_new </lang>

Output:

Mary had a X lamb.
Mary had a little lamb.

UNIX Shell

Works with: Bourne Shell

Within the Unix shell, interpolation only occurs within doublequotes. Strings enclosed in singlequotes will not be subject to interpolation. Note that within the shell, a string may be used bare. If this is done each word within the string is treated separately, and any variable references or escape sequences will be substituted for their values:

<lang sh>extra='little' echo Mary had a $extra lamb. echo "Mary had a $extra lamb." printf "Mary had a %s lamb.\n" $extra</lang>

A parameter substitution, like $extra or ${extra}, interpolates its value into some string. This happens outside quotes or inside "double quotes". The other form of interpolation is printf(1) with %s.

The shell has more forms of parameter substitution, like ${tea:?no tea}. Your shell's manual explains those. For the original Bourne Shell, sh(1) manual explains those.

C Shell

<lang csh>set extra='little' echo Mary had a $extra lamb. echo "Mary had a $extra lamb." printf "Mary had a %s lamb.\n" $extra</lang>

C Shell has $extra and ${extra}. There are also modifiers, like $file:t; csh(1) manual explains those.

Ursala

Expressions like this <lang Ursala>-[foo-[ x ]-bar]-</lang> evaluate to a list of character strings beginning with foo and ending with bar, where foo and bar are literal text (possibly multiple lines) and x is any expression evaluating to a list of character strings. Using a dot like this <lang Ursala>-[foo-[. f ]-bar]-</lang> makes it a function returning a list of character strings consisting of the output from the function f bracketed by the literal text foo and bar. In this task, the identity function, ~&, is used for f. <lang Ursala>x = <'little'>

show+

main = -[Mary had a -[. ~& ]- lamb.]- x</lang> These operators are parsed like parentheses.

Output:

Mary had a little lamb.

Vala

<lang vala>void main() {

 string size = "little";
 print(@"Mary had a $size lamb\n");
 stdout.printf("Mary had a %s lamb\n", size);

}</lang>

Output:

Mary had a little lamb
Mary had a little lamb

VBA

Here are 2 examples:

With Replace

a="little"
debug.print replace("Mary had a X lamb","X",a)  'prints Mary had a little lamb

Replace

With Interpolation function

Sub Main()
    a="little"
    debug.print Format("Mary had a {0} lamb",a)
End Sub

Public Function Format(ParamArray arr() As Variant) As String
    Dim i As Long, temp As String
    temp = CStr(arr(0))
    For i = 1 To UBound(arr)
        temp = Replace(temp, "{" & i - 1 & "}", CStr(arr(i)))
    Next
    Format = temp
End Function

CStr UBound ParamArray

Verbexx

<lang verbexx>//////////////////////////////////////////////////////////////////////////////////////// // // The @INTERPOLATE verb processes a string with imbedded blocks of code. The code // blocks are parsed and evaluated. Any results are converted to a string, which // is then inserted into the output string, replacing the code and braces. // // example: @INTERPOLATE "text{ @IF (x > y) then:{x} else:{y} }more text " // ////////////////////////////////////////////////////////////////////////////////////////

@VAR v = "little";

@SAY (@INTERPOLATE "Mary had a { v } lamb");

// output: Mary had a litle lamb</lang>

Visual Basic .NET

<lang vbnet> Dim name as String = "J. Doe" Dim balance as Double = 123.45 Dim prompt as String = String.Format("Hello {0}, your balance is {1}.", name, balance) Console.WriteLine(prompt) </lang>

Wren

<lang javascript>var s = "little" var t = "Mary had a %(s) lamb" System.print(t)</lang>

Output:

Mary had a little lamb