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sassmixins

Can you test if a mixin exists?

Sass quick question (hopefully) here. Can you test for the existence of a mixin? e.g. 

@if thumbnail-mixin {} @else { //define mixin }.

Ideally I'd use @unless, but that only exists on a fork. I'm aware you can overwrite a mixin but I'm thinking more if you can have a default mixin, rather than having to specify N variables in every case.

Solution

  • Sass does not currently have native functionality to determine if a mixin exists or not.

    https://github.com/nex3/sass/issues/561#issuecomment-14430978

    You could create a Sass function written in Ruby:

    def mixin_exists(mixin_name)
    if(environment.mixin(mixin_name.value))
      Sass::Script::Bool.new(true)
    else
      Sass::Script::Bool.new(false)
    end
end

    Or you could use the sass-utilities Compass extension, which has this function included.