SASS Mixin — Single/double colon generated content

mixin-before-after.scss

@mixin before-after {
    @if $old-ie {
        &:before, &:after {
            @content;
        }
    } @else {
        &::before, &::after {
            @content;
        }
    }
}
@mixin before {
    @if $old-ie {
        &:before {
            @content;
        }
    } @else {
        &::before {
            @content;
        }
    }
}
@mixin after {
    @if $old-ie {
        &:after {
            @content;
        }
    } @else {
        &::after {
            @content;
        }
    }
}