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Question

Given a string as input, output a number of whitespace characters (0x0A and 0x20) equal to the length of the string.

For example, given the string Hello, World! your code would need to output exactly 13 whitespace characters and nothing else. These can be any mix of spaces and newlines.

Your code should not output any additional trailing newlines or spaces.

Testcases:

 Input -> Amount of whitespace to output
"Hello, World!" -> 13
"Hi" -> 2
" Don't
Forget about
Existing
Whitespace! " -> 45
"" -> 0
" " -> 13
"
" -> 1

Scoring:

This is code-golf so fewest bytes wins!

• manatwork: I don't get what you mean with that "0x0A". Where should that be output? Should that be kept, so "a␠b␊c" becomes "␠␠␠␊␠"?
• Mayube: @manatwork 0x0A and 0x20 are the hexadecimal values for the Newline and Space characters respectively
• manatwork: "output a number of whitespace characters (0x0A and 0x20)" – Where in the output should those newline characters be?
• Mayube: These can be any mix of spaces and newlines Your output can be any mix of spaces and newlines, you can just output spaces if you want, like everyone else, or you can just output newlines. It's up to you
• Luis Mendo: Can we assume the input will only have printable characters?

Answer 1

TXR Lisp, (削除) 22 (削除ここまで) 19 bytes:

(op regsub #/./" ")

Previously:

(op mapcar(ret[" "0]))

That is a function to which we can pass a string:

REPL:

1> (op regsub #/./" ")
#<interpreted fun: lambda #:rest-0164>
2> [*1 "abc"]
" "
" "

Answer 2

Clojurescript, 27 bytes

#(apply str(map(fn[]" ")%))

Because it's based on js, clojurescript doesn't care about arity errors. That saves one byte over the clojure eqivalent.

Answer 3

Windows batch, 115 bytes

@set i=%~1
@set p=0
@set/ac=-1
:N
@call set t=%%i:~%p%,1%%
@set/ac+=1
@set/ap+=1
@if "%t%" NEQ "" @goto N
@echo %c%

Re-used code from my answer in Is the checkbox not not unchecked?

Answer 4

Bash + Coreutils, 11 Bytes

tr -c \ \

Answer 5

Powershell, 22 Bytes

' '*(Read-Host).length

• Matt: Not sure if Read-Host counts for input but " "*"$args".length is shorter anyway. Also there is not len property. That should be printing nulls.
• Sivaprasath Vadivel: Length property and Len are same
• Matt: "hello".Len is null on my system because that is a non-existent property where as "hello".Length returns 5. If that works for you then you have an alias or extent that I, and most, do not have.
• Sivaprasath Vadivel: Ok...That explains it

Answer 6

Ruby, (削除) 12 (削除ここまで) 11+1 = (削除) 13 (削除ここまで) 12 bytes

Uses the -p flag. -1 byte from Martin Ender.

gsub /./,$/

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Answer 7

J, 6 bytes

' '#~#

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Explanation

' '#~#
 #~ repeat
' ' spaces
 # for length of input

• FrownyFrog: 4 bytes ''"0 outputs n newlines.
• Conor O'Brien: @FrownyFrog You should make your own answer, it's quite different from mine

Answer 8

Common Lisp, 32 bytes

(format t"~va"(length(read))#\ )

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Answer 9

Carrot, 12 bytes

#^//()/gS" "

Try it online! (append a ^@^v@ after the code to see the spaces bounded between @s)

Explanation

#^ Set the stack-string to be equal to the input
/ Get matches of this regex
 /()/g any position (not character) in the string (shorter than /\b|\B/ by 3 bytes)
 If the length of the string is 3, this returns a 4-element array
 consisting of empty strings
S" " Join on spaces, so the example 4-element array will result in 3 spaces

The space can even be replaced with a literal newline or tab for the same bytecount.

Answer 10

Ly, 9 bytes

iy[' o,];

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Explanation:

iy[' o,];
iy # push length of input
 [ ] # while loop
 ' o # output a space
 , # decrement input length
 ; # terminate (avoids implicit output)

Answer 11

Jq 1.5, (削除) 69 (削除ここまで) (削除) 68 (削除ここまで) (削除) 66 (削除ここまで) 64 bytes

def L:length;$x|if L<1then empty elif L<2then""else L-1|.*" "end

This is longer then usual to compensate for newline jq normally emits and the odd behavior of * with N<2

Sample runs:

$ jq -Mrn --arg x 'Hello, World!' 'def L:length;$x|if L<1then empty elif L<2then""else L-1|.*" "end'
$ jq -Mrn --arg x 'Hello, World!' 'def L:length;$x|if L<1then empty elif L<2then""else L-1|.*" "end' | wc -c
 13
$ echo -n 'def L:length;$x|if L<1then empty elif L<2then""else L-1|.*" "end' | wc -c
 64

Shout out to Jonathan Frech for finding 3 superfluous spaces!

• Jonathan Frech: I do not know jq, but as then""else is syntactically valid, it seems like you could also omit the space in " " end.
• Jonathan Frech: As variables probably cannot begin with a digit, the spaces in <1 then and <2 then may also be superfluous.

Answer 12

Vim, 4 bytes

VGr 

(a trailing space)

Answer 13

Yabasic, 37 bytes

Takes input, and outputs as many new lines as the length of the input

Line Input""s$
For i=1TO Len(s$)?Next

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Answer 14

C# .NET, 84 bytes

class P{static void Main(string[]a){System.Console.Write("".PadLeft(a[0].Length));}}

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Answer 15

Kotlin, 20 bytes

{" ".repeat(length)}
{" ".repeat // repeat space
 (length)} // length of input

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Answer 16

Forth (gforth), 9 bytes

typewhite

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It is a gforth built-in. A string in gforth is commonly represented as addr length, and typewhite consumes addr length and prints length spaces.

• Razetime: forth golfing language confirmed?!

Answer 17

Add++, 21 bytes

D,f,@@,bL*
$f>" ">?
o

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Answer 18

Check, 6 bytes

," "*o

Pass the input by the command-line arguments as a list of code points, i.e. [72,101,108,108,111,44,32,87,111,114,108,100,33].

Explanation:

• , gets the length of the input.
• " " pushes an array containing 32 (for space).
• * repeats that array as many times as the length of the input.
• o displays the result as a list of characters.

Answer 19

Vyxal, 3 bytes

Lð*

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Command-line usage:

python3 Vyxal.py file_name "" input_string

Explained

L # Push the length of the implicit input
 ð # Push a space character
 * # Multiply that space by the length and output.

Answer 20

Duocentehexaquinquagesimal, 7 bytes

×ばつ^c¤E

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Answer 21

Factor, 20 bytes

[ [ drop bl ] each ]

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For each character in the input string, drop it from the data stack and output a space.

Answer 22

Fig, \4ドル\log_{256}(96)\approx\$ 3.292 bytes

;M/ 

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Note the space at the end.

;M/<space>
;M # Replace all in the input
 /<space> # With a space
; # Print without newline

• Dominic van Essen: Are you sure this doesn't output a trailing newline? This is what it looks like when I run it... (I only checked because the same annoying thing was happening for my own attempt in Nibbles...)
• Seggan: @DominicvanEssen ah yes, it does output with a newline. I missed that part of the spec. will update
• Dominic van Essen: If you can use the same code in the context of a function, maybe the returned string would be Ok...
• Seggan: @DominicvanEssen all the other golflang answers seem to do that too...

Answer 23

Pascal, 82 B

This program merely requires a processor complying to ISO standard 7185 "Pascal". Since it is not guaranteed that writeLn produces exactly one character (on some platforms the line separator is CR+LF), we’ll have to use write(' '):

program p(input,output);begin while not EOF do begin write(' ');get(input)end end.

If input was simply a string value, when an ISO standard 10206 "Extended Pascal" processor is used the following is the shortest solution (≥ 24 B):

writeStr(outputStringVariable, '':length(inputMyString))

The :someNonNegativeIntegerValue after the empty string '' will (left) pad the given argument to the specified width using space characters (' '). A complete demonstration:

program paddingDemo(output); begin write('':length('Hello, World!')) end.

Answer 24

Thunno, \$ 6 \log_{256}(96) \approx \$ 4.94 bytes

L1-A_*

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Note: A\ will also work instead of A_ if you want newlines rather than spaces.

Explanation

L1-A_* # Implicit input
L # Length
 1- # Minus one
 * # Multiplied by
 A_ # A space
 # Implicit print
 # with a newline

Answer 25

Thunno 2, 3 bytes

l−ṣ

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Explanation

l−ṣ # Implicit input
l # Length
 − # Decrement
 ṣ # Spaces
 # Implicit output with newline

Answer 26

Swift 6, 36 bytes

{{String.init}()(" ",(0ドル+"").count)}

To use this, assign it to something and then call that thing:

let whitespace = {{String.init}()(" ",(0ドル+"").count)}
print(whitespace("Hello, world!"), terminator: "")
// Prints " "

The {String.init}() trickery simply gives us a reference to String.init(repeating:count:), but without the costly argument labels. Appending an empty string to 0ドル (the implicit closure parameter) informs the type checker that 0ドル is a String.