functions.scss

@function hello($x) {
    @return $x + 4;
}

@function add($a, $b) {
    @return $a + $b;
}

div {
    color: hello(10px);
    sum: add(11, 12);
}

// make sure values are being reduced before being passed up to previous scope

@function one($a, $b) {
    @return $a $b;
}

@function two($a, $b) {
    @return $a#{$a} $b;
}

@function three($a, $b: default) {
    @return "hello #{$a} and #{$b}"
}

@function all($a...) {
    @return "hello #{$a}"
}

div {
    hello: one(10, 55);
    hello: two(10, 55);
    hello: three(10, 55);
}


@function hello_world() {
    @return 1000;
}

del {
    color: hello-world();
}

div {
    $args: foo bar;
    hello: three($args...);
    hello: three(bar...);
    hello: all(Alice, Bob, Tom);
}

@function stringConcatCompassStyle($start,$last)
{
    // Compass still uses it like this
    @return #{$start}-#{$last};
}

.foo
{   
    test2: stringConcatCompassStyle(-moz,art);
}

@mixin content_test {
    span {
        $color: green;
        @content;
    }
}

@function func_test($c) {
    @return $c + 1;
}

div {
    @include content_test {
        height: func_test(2px);
    }
}

@function test ($a, $b: $a/2) {
    @return $b;
}

div {
  width: test(4);
}

@function test($args...){
    @return type-of($args); // should return arglist, but returns list
}

p{
    color: test("a", "s", "d", "f");
}

@function test-function() {
  $str: 'test-function';
  @return $str;
}

@mixin test-mixin {
  $str: 'test-mixin';
  display: $str;
  $new-bp: test-function();
  display: $str;
}

$str: 'global';
.test{
  display: $str;
  @include test-mixin;
  display: $str;
}

.test-inspect {
  n: inspect(null);
  b1: inspect(true);
  b2: inspect(false);
  n1: inspect(0);
  s1: inspect('');
  s2: inspect('hello');
  l1: inspect(1 2);
  l2: inspect((3 4));
  l3: inspect((5,6));
  l4: inspect((a: 1, b: 2));
  l5: inspect($value: (a: 1, b: 2));
}

@function contains($list, $values...) {
  @each $value in $values {
    @if type-of(index($list, $value)) != "number" {
      @return false;
    }
  }

  @return true;
}

@function mapping($items) {
  $src: ();
  $map: (
          one:   1px 1px,
          two:   2px 2px,
  );

  @each $key, $values in $map {
    @if contains($items, $key) {
      $value1: nth($values, 1);
      $value2: nth($values, 2);

      $src: append($src, $value1 $value2, space);
    }
  }

  @return $src;
}

@mixin test() {
  padding: mapping(one two);
}

div {
  margin: mapping(one two);
  @include test();
}

$a: rgba(#000, 0.5);
$b: rgba(#fff, 0.75);

.test {
    color: mix($a, $b);
}