generate classes from Scss / Sass nested map - sass

Question

How does one generate a list of classes for each key that has a single value inside a Scss/Sass map?
For example, from this Scss map (disregard nested naming conventions, this will be used for many maps of varying purposes):
(See Codepen: http://codepen.io/harlanlewis/pen/emWVrr (thanks cimmanon!))
$palette: (
brown: hsl(33,35,50),
blue: hsl(207,80,50),
green: (
0: hsl(157,65,65),
1: hsl(157,50,50),
alt: (
0: hsl(125,65,65),
),
),
red: (
0: hsl(0,60,50),
alt: (
0: hsl(0,100,50),
),
),
yellow: (
0: hsl(50,100,60),
1: hsl(50,100,100),
),
};
-
#mixin map-to-class($map, $selector: '', $property: '') {
$selector: if($selector == '' and &, &, $selector);
#each $key, $value in $map {
#if type-of($value) == map {
$selector: selector-append($selector, #{$key});
#include map-to-class($value, $selector, $property) {
#content;
}
} #else {
#at-root #{$selector}#{$key} {
#{$property}: $value;
};
};
};
};
#include map-to-class($palette, '.u-fg__', 'color')
...desired classes to generate:
.u-fg__brown { color: hsl(33,35,50) }
.u-fg__blue { color: hsl(207,80,50) }
.u-fg__green0 { color: hsl(157,65,65) }
.u-fg__green1 { color: hsl(157,50,50) }
.u-fg__greenalt0 { color: hsl(125,65,65) }
.u-fg__red0 { color: hsl(0,60,50) }
.u-fg__redalt0 { color: hsl(0,100,50) }
.u-fg__yellow0 { color: hsl(50,100,60) }
.u-fg__yellow1 { color: hsl(50,100,80) }
The actual (incorrect) generated classes are: (note greenredyellow instead of just yellow)
... (brown, blue, and green are fine) ...
.u-fg__green0 { color: hsl(157,65,65) }
.u-fg__green1 { color: hsl(157,50,50) }
.u-fg__greenalt0 { color: hsl(125,65,65) }
.u-fg__greenred0 { color: hsl(0,60,50) }
.u-fg__greenredalt0 { color: hsl(0,100,50) }
.u-fg__greenredyellow0 { color: hsl(50,100,60) }
.u-fg__greenredyellow1 { color: hsl(50,100,80) }

Answer 1

What you're looking for is a recursive mixin. Walk through the mapping. If the value is a mapping, call itself otherwise print out the property/value.
$palette: (
'brown': hsl( 33, 35, 50),
'blue': hsl(207, 80, 50),
'green': (
0: hsl(157, 65, 65),
1: hsl(157, 50, 50),
alt: (
0: hsl(125, 65, 65),
),
),
'red': (
0: hsl(0, 60, 50),
alt: (
0: hsl(0, 100, 50),
),
),
'yellow': (
0: hsl(50, 100, 60),
2: hsl(50, 100, 100),
),
);
#mixin map-to-class($map, $property, $sel, $divider: '') {
$sel: if($sel == '' and &, &, $sel);
#debug $sel;
#{$sel} {
#each $k, $v in $map {
#at-root #{$sel}#{$divider}#{$k} {
#if type-of($v) == map {
#include map-to-class($v, $property, '', $divider) {
#content;
}
} #else {
#{$property}: $v;
}
}
}
}
}
#include map-to-class($palette, color, '.u-fg__', '');
Output:
/* line 33, ../sass/test.scss */
.u-fg__brown {
color: #ac8453;
}
/* line 33, ../sass/test.scss */
.u-fg__blue {
color: #198ae6;
}
/* line 33, ../sass/test.scss */
.u-fg__green0 {
color: #6ce0b3;
}
/* line 33, ../sass/test.scss */
.u-fg__green1 {
color: #40bf8e;
}
/* line 33, ../sass/test.scss */
.u-fg__greenalt0 {
color: #6ce075;
}
/* line 33, ../sass/test.scss */
.u-fg__red0 {
color: #cc3333;
}
/* line 33, ../sass/test.scss */
.u-fg__redalt0 {
color: red;
}
/* line 33, ../sass/test.scss */
.u-fg__yellow0 {
color: #ffdd33;
}
/* line 33, ../sass/test.scss */
.u-fg__yellow2 {
color: white;
}
Note that I quoted your mapping key names. Sass will convert those to their hex code equivalents under certain compression types.