// ## Spacer
// Using this function requires that the value passed be a multiple of .5
// This encourages greater spacing consistentcy. The following example
// will output 25px. It will test to see if value is multiple of .5. If not
// it will provide a warning.

// Usage:

// [c]
//     padding: spacer(2.5);
// [/c]

@function spacer($value) {
  @if ($value * 2) % 1 != 0 {
    @warn 'Spacer value must be a multiple of 0.5';
    @return 'Spacer value must be a multiple of 0.5';
  } @else {
    @return $spacer-unit * $value;
  }
}

// ## Map Fetch
// Retrieves values from any map, nested or not.
// Adapted from https://gist.github.com/jlong/8760275 - added errors.

@function map-fetch($map, $keys) {
  $key: nth($keys, 1);
  $length: length($keys);
  $value: map-get($map, $key);
  @if ($length > 1) {
    $rest: ();
    @for $i from 2 through $length {
      $rest: append($rest, nth($keys, $i));
    }
    @if ($value == null) {
      @error "The value '#{$key}' doesn't exist in the map.";
    }
    @return map-fetch($value, $rest)
  } @else {
    @if ($value == null) {
      @error "The value '#{$key}' doesn't exist in the map.";
    }
    @return $value;
  }
}

// ## Map Extend
// Extends Sass maps.
// Adapted from http://www.sitepoint.com/extra-map-functions-sass/

@function map-extend($map, $maps...) {
  $max: length($maps);
  @for $i from 1 through $max {
    $current: nth($maps, $i);
    @each $key, $value in $current {
      @if type-of($value) == 'map' and type-of(map-get($map, $key)) == 'map' {
        $value: map-extend(map-get($map, $key), $value);
      }
      $map: map-merge($map, ($key: $value));
    }
  }
  @return $map;
}