Generated by SassMeister.com.

SassMeister-input.sass

// ----
// Sass (v3.3.0.rc.1)
// Compass (v0.13.alpha.10)
// ----

=extend-variants($module_name, $variants...)
    @each $variant in $variants
        @if type_of($variant) == "list"
            $variant: #{nth($variant, 1)}--#{nth($variant, 2)}
        @extend %#{$module_name}%-#{$variant}
=extend($module_name, $variants...)
    @extend %#{$module_name}
    +extend-variants($module_name, $variants...)


%comp
    color: blue

    &%-flag
        %subcomp
            color: orange

%subcomp
    color: yellow

.a
    +extend(comp)
.a_1
    +extend(subcomp)
.b
    +extend(comp, flag)
.b_1
    +extend(subcomp)

.c
    +extend(comp, flag)
.c_1
    +extend(subcomp)

SassMeister-output.css

.a, .b, .c {
  color: blue;
}
.b .a_1, .c .a_1, .b .b_1, .c .b_1, .b .c_1, .c .c_1 {
  color: orange;
}

.a_1, .b_1, .c_1 {
  color: yellow;
}