compact() removed from libsass 3.0.1

[kjbbb]

A recent change in libsass broke compass compatibility by removing the compact() function... The function was removed because it's not in the sass spec.

sass/libsass@003d3dc

[Zauberfisch]

I hot fixed this issue by adding this function:

@function compact($var-1, $var-2: false,
$var-3: false, $var-4: false,
$var-5: false, $var-6: false,
$var-7: false, $var-8: false,
$var-9: false, $var-10: false) {
    $full: $var-1;
    $vars: $var-2, $var-3, $var-4, $var-5,
    $var-6, $var-7, $var-8, $var-9, $var-10;

    @each $var in $vars {
        @if $var {
            $full: $full, $var;
        }
    }
    @return $full;
}

taken from http://stackoverflow.com/a/11752227

[Zauberfisch]

I have to correct my earlier statement. It did not solve all problems, While I was no longer getting errors, I noticed that the css output was no longer valid. With the above function I was getting things like:

/* from @include transition(opacity 3000ms ease); it generated: */
-webkit-transition: opacity false false, 3000ms false false, ease false false;
-moz-transition: opacity false false false, 3000ms false false false, ease false false false;
-o-transition: opacity false false false, 3000ms false false false, ease false false false;
transition: opacity 3000ms ease;

I have written my own compact function now, which seems to solve the problem (though its pretty late, so I might be missing something).
It loops the list recursively to ensure all false-ish values are removed.

@function _compact($var) {
    @if type_of($var) == 'list' {
        $full: ();
        @each $item in $var {
            @if $item {
                $full: append($full, _compact($item));
            }
        }
        @return $full;
    }
    @return $var;
}

@function compact($var-1, $var-2: false, $var-3: false, $var-4: false, $var-5: false, $var-6: false, $var-7: false, $var-8: false, $var-9: false, $var-10: false) {
    @return _compact(($var-1, $var-2, $var-3, $var-4, $var-5, $var-6, $var-7, $var-8, $var-9, $var-10));
}

PS: please note that there also has been bug (sass/libsass#254) reported recently about false-ish values that are not evaluated as false which might effect the outcome of this function. that might cause issues with this code, but does not seem to be the case/has been fixed in latest master.

[mikob]

Both of those were giving me issues by not putting commas between multiple box-shadow properties. This works for me:

@function compact($vars...) {
    $list: ();
    @each $var in $vars {
        @if $var {
            $list: append($list, $var, comma);
        }
    }
    @return $list;
}

[elsigh]

I had this issue as well.

[michaek]

I saw that in the release notes, and thought of this as well. I think the functions above may make sense to include to resolve the problems. Is there a PR?

[mikob]

@michaek I never made one.

[Igosuki]

I'm adding @mikob's function to the new release.

[adalinesimonian]

@Igosuki +1 That's great news! I've been relying on a separate _compact.scss and it'd be great to finally dump that li'l old thing. 😃

[Igosuki]

Done in v0.12.7

[bmiller59]

I had an issue with recursive compact arguments. It was leaving false items in. I combined the above solutions and this fixed it:

@if not(function-exists(compact)) {
  @function compact($vars...) {
    @each $var in $vars {
      @if type_of($var) == 'list' {
        $full: ();
        @each $item in $var {
          @if $item {
            $full: append($full, compact($item), comma);
          }
        }
        @return $full;
      }
      @return $var;
    }
    @return $vars;
  }
}

[Igosuki]

So this is a bug with the current version (0.12.7) ?

[mikko-h]

Yes, it is a bug in 0.12.7. mikob's implementation used in 0.12.7 leaves extraneous falses to the output like: -moz-transition: opacity 0.2s false false; However bmiller59's implementation has also a bug, it generates an extra comma when it is not needed, like: -moz-transition: opacity, 0.2s; Correct output should be: -moz-transition: opacity 0.2s;

EDIT: This works for me:

@function compact($vars...) {
    $first: nth($vars, 1);
    $sep: comma;
    $list: ();
    @if length($vars) == 1 and type_of($first) == 'list' {
        $vars: $first;
        $sep: list-separator($vars);
    }
    @each $var in $vars {
        @if $var {
            $list: append($list, $var, $sep);
        }
    }
    @return $list;
}

I got inspiration from the original ruby implemenation: https://github.com/Compass/compass/blob/master/core/lib/compass/core/sass_extensions/functions/lists.rb#L17

[Igosuki]

Closely implementing the ruby function is how it should be done in the first place, thanks.

[thejmazz]

Wish I came across this sooner..have spent the past hour or so pulling my hair over the fact that my simple @include box-shadow was not working. So far @mikko-h's solution has worked for me.

[bjudson]

I'm still getting incorrect output with version 0.12.7. For example the Sass:
+transition(all 0.25s ease-in)

Yields:

-webkit-transition: all;
-moz-transition: all;
-o-transition: all;
transition: all;

I get the same output when I replace compact() with @mikko-h's solution.

[leochen1216]

Same here. I'm using 0.12.7.

@include transition(max-height .2s);

output:

 -webkit-transition: max-height;
  -moz-transition: max-height;
  -o-transition: max-height;
  transition: max-height;

[leochen1216]

This version (#67) works for both single & multiple transitions:

@function compact($args...) {
    $first: nth($args, 1);
    $sep: comma;
    $list: ();

    @if length($args) == 1 and type_of($first) == 'list' {
      $args: $first;
      $sep: list-separator($args);
    }

    @for $index from 1 through length($args) {
      $arg: nth($args, $index);

      @if $arg {
        $list: append($list, $arg, $sep);
      }
    }

    @return $list;
  }

[iampuma]

Had the same problem with @include background(#ccc);

Above solution of leochen1216 works.

[acha5066]

Can confirm that leochen1216 also fixed my issue with @include background(#ccc). Excuse my ignorance but why was this function deprecated in a minor release?

[linibou]

leochen1216 function's works perfectly for me, thank you ! issue with @include single-transition(border, .2s, ease-in);

[xzyfer]

Fixed in v0.12.8

[halfnibble]

How is this fixed, exactly?

Shouldn't the reimplementation of compact() be in "shared" or some other file that all scripts source?

[afoeder]

I am also troubled by the lack of the compact() function... functions/_lists.scss says on line 7,

// compact is part of libsass

but when googling for that it seems it has somehow removed from libsass?
What's the state of this now?

Thanks!