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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!

Answer 1

Cubix, 6 bytes

Wahoo a 6 byter!

wi?@oS

Cubified

  w
i ? @ o
  S

• i gets input
• ? test top of stack
  • if negative (EOI) redirect onto w lane change which umps to the @ halt
  • if 0 (null) halt this shouldn't be hit
  • if positive Sow push space to the stack, output and change lane onto i

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Answer 2

C, 32 bytes

Try Online modifying characters into spaces

f(char*t){(*t=*t?32:0)&&f(t+1);}

C, 37 bytes

Try Online Left-padding the end-of-string with its length

f(char*t){printf("%*c",strlen(t),0);}

Answer 3

APL (Dyalog) 13.2, 1 byte

Prints only spaces.

∊ prototype (numbers become zeros, characters become spaces)

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Answer 4

Pepe, 46 37 bytes

REEeRREeeeREEEEErEeeEeeeeerEEeeeEreee

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Explanation:

REEe       # Input (string) in R
RREeee     # Push reverse pointer position, or length of input - 1
           # R flag: push in beginning
REEEEE     # ...add 1
rEeeEeeeee # Push space in r
rEEeeeE    # ...R times
reee       # Output whole stack

Answer 5

Poetic, 81 bytes

the berenstein bears
i remember a series i spelled wrong
o m gee,i do remember it

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The misspelling is intentional. (...or is it?)

Answer 6

Gema, 4 characters

?=\ 

(There is a space at the end of code.)

Sample run:

bash-4.4$ echo -n 'Hello, World!' | gema '?=\ '
             bash-4.4$ echo -n 'Hello, World!' | gema '?=\ ' | wc
      0       0      13

Answer 7

APL (Dyalog), 3 bytes

Prints only newlines.

0/⍪

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⍪ table (makes string into column matrix)

0/ replicate each column zero times

Answer 8

Scala, 15 bytes

s=>" "*s.length

Answer 9

Java 8, 24 bytes

s->s.replaceAll("."," ")

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Java 7, 49 bytes

String c(String s){return s.replaceAll("."," ");}

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Answer 10

Chip, 2 bytes

*f

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Chip reads in a byte, does whatever calculations are in the code, and writes a byte. So, for each byte of input, we ignore the input and write 0x20 instead. The empty Chip program would replace each byte of input with a null byte of output.

*    Source element, activates any neighbor elements
 f   Output element for the bit 0x20, when active this bit is set in the output

Transposing the two characters would result in the same thing. I opted to use spaces, since 0x20 requires only one bit to be set. 0x0a requires setting two bits. Code for that could be:

b*d

Answer 11

Shell utils, 14 12 bytes

tr ' -~' ' '

tr translates characters in the first parameter, into the corresponding one in the second parameter. (space)-~ is a range for space (32) to tilda (126), the first and last printable ASCII characters. They are mapped into a space; tr duplicates the last character in the output list if it is shorter than the input list.

Answer 12

shortC, 16 bytes

f(C*a){W*a++)P' 

Note the trailing space at end of code.

Conversions in this program:

• C -> char
• W -> while(
• P -> putchar(

The resulting program looks like this:

f(char *a){while(*a++)putchar(' ');}

How that works:

• while(*a++) loops until it reaches the last index of the string a.
• putchar(' '); prints a space for each index of a.

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Answer 13

dc, 25 18 bytes

-1 byte thanks to brhfl

Z[1-d0<L32P]sLd0<L

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Explanation:

Z[1-d0<L32P]sLd0<L
                    Implicit input
Z                   Get length
 [         ]sL      Create a funcion and saves in L
              d0<L  If length > 0, call L
  1-                Subtract 1 from the length
    d0<L            If length > 0, call L
        32P         Print space

Answer 14

Ruby -p, 10 bytes

$_=$/*~/$/

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Explanation:

$_=          Output equals
   $/        the output separator (defaults to newline)
     *       repeated a number of times equal to
      ~      the index in the input of the first match of
        /$/  the regular expression for "end of line"

Answer 15

Powershell, 18 12 bytes

-6 bytes thanks @Julian

$args|%{' '}

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Testscript (use LF only mode in your editor):

$f = {
$args|% t*y|%{' '}
}

@(
,(13, "Hello, World!")
,(2, "Hi")
,(45, "   Don't
Forget about
Existing
Whitespace!   ")
,(0, "")
,(13, "             ")
,(1,"
")
) | % {
    $len,$source=$_
    $r = &$f $source
    $l=$r.length
    "$($l-eq$len): $l"
}

Output:

True: 13
True: 2
True: 45
True: 0
True: 13
True: 1

Powershell + Regex, 20 bytes

$args-replace'.',' '

Answer 16

Trilangle, 11 bytes

i7#'@"o.:2L

Unfolds to this:

    i
   7 #
  ' @ "
 o . : 2
L . . . .

This has to be the most creative way I've used @ yet: when hit in one direction, it ends the program; when hit in a different direction, it's divided by 2 to get a space.

Roughly equivalent to this C code:

#include <stdio.h>

int main() {
    while (getchar() != EOF) {
        printf(" ");
    }
}

Answer 17

Perl 6, 10 bytes

{S:g/./ /}

Basic string substitution.

Answer 18

JavaScript (ES8), 22 bytes

s=>"".padEnd(s.length)

Answer 19

Convex, 2 bytes

,*

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Simply takes the length of the input and multiplies by newlines (which are at the bottom of the stack)

Answer 20

Bash, 16 bytes

printf %*s ${#1}

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Uses parameter expansion count the length of the argument ${#1}, and then printf to output an empty string space-padded to that same length.

Answer 21

PowerShell, 21 bytes

[char[]]"$args"|%{""}

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prints newlines.

Answer 22

APL, 11 6 bytes

5 bytes saved thanks to @Adám

' '⍴⍨≢

Uses the Dyalog Classical character set.

Answer 23

Perl 5, 6 + 1 = 7 bytes

Uses the -p flag.

y// /c

y/// is the transliteration operator: the first list is translated to the corresponding character in the second list. Without the c, this does nothing, but the c complements the first list, so all characters are transliterated to a space.

Answer 24

Aceto, 5 bytes

Trivial in Aceto:

p
,'O

Reads a character, pushes a space, prints it, and goes back to the start.

Answer 25

T-SQL, 32 bytes

SELECT SPACE(LEN(a+'x')-1)FROM t

Microsoft SQL's LEN function ignores trailing spaces, so this hacky workaround is required.

Input is stored in varchar column a in pre-existing table t, per our input rules.

Answer 26

q/kdb+, 14 9 bytes

Solution:

{" "}each

Example:

q){" "}each"Hello, World"
"            "

Explanation:

Returns " " for each character of the input.

Notes:

I've made a shorter version (7 bytes) that does something similar:

{y}'" "

... but you have to prepend the input rather than append:

q)"hello world"{y}'" "
"           "

Answer 27

TI-Basic, 13 bytes

For(I,2,length(Ans
Disp "
End

Loop starts at 2 because an additional newline is printed before Done at the end of the program.

Answer 28

MATL, 3 4 bytes

nqZ"

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Today I learnt that MATLAB has a function for creating a string of spaces!

n - count the number of bytes in input string
q - decrement by 1, because the implicit disp at the end adds a newline (so the number of spaces required is string length - 1)
Z" - blanks command: create a string with the specified number of spaces in it
(Implicit output at end, with trailing newline.)

Answer 29

R, 37 23 bytes

gsub("."," ",scan(,""))

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14 bytes saved by ngm.

Answer 30

J, 4 bytes

LF"0

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Converts each cell (each character in this case) to the linefeed character. LF is a built-in noun for '\n'. "0 attached to a noun converts it to a verb with the given rank.