你有很多事情发生在这里并不完全正确。
// If this is part of a reusable library, use the default flag
// I typically prefer prefixing global variables to avoid collisions with other code
// (eg. $grid-colCount instead of $colCount)
$colCount: 2 !default;
$colSpan: 1 !default;
$gutter: 4% !default;
// Mixin changed to a function, better for its intended purpose
@function width($colCount: $colCount, $colSpan: $colSpan, $gutter: $gutter) {
@return $colSpan * ((100% - $gutter) / $colCount);
}
// The arguments are set to our global variables by default
@mixin columns($colCount: $colCount, $colSpan: $colSpan, $gutter: $gutter) {
@content;
// Something weird was going on here that just plain didn't compile
width: width($colCount, $colSpan, $gutter);
&.first {
// This is where your mixin was getting messed up,
// it wasn't passing the values it received on to the mixins
@include first($colCount, $colSpan, $gutter);
}
&.only {
@include only($colCount, $colSpan, $gutter);
}
&.firstOnly {
@include firstOnly($colCount, $colSpan, $gutter);
}
}
@mixin first($colCount: $colCount, $colSpan: $colSpan, $gutter: $gutter) {
margin-left: 100% - width($colCount, $colSpan, $gutter);
}
@mixin only($colCount: $colCount, $colSpan: $colSpan, $gutter: $gutter) {
margin-left: 100% - (2 * width($colCount, $colSpan, $gutter)) - (2 * $gutter);
}
@mixin firstOnly($colCount: $colCount, $colSpan: $colSpan, $gutter: $gutter) {
margin-left: 100% - width($colCount, $colSpan, $gutter) - $gutter;
margin-right: 100% - width($colCount, $colSpan, $gutter);
}
当我们这样调用 mixin 时:
.test {
@include columns(3, 8, 40%);
}
.test2 {
@include columns;
}
我们得到这个结果:
.test {
width: 160%;
}
.test.first {
margin-left: -60%;
}
.test.only {
margin-left: -300%;
}
.test.firstOnly {
margin-left: -100%;
margin-right: -60%;
}
.test2 {
width: 48%;
}
.test2.first {
margin-left: 52%;
}
.test2.only {
margin-left: -4%;
}
.test2.firstOnly {
margin-left: 48%;
margin-right: 52%;
}