Sass: Function to render a "begins with" selector, which matches elements with some class beginning with a given text

gistfile1.scss

@function class-begins-with($class-name){
    @return '[class^="#{$class-name}"], [class*=" #{$class-name}"]';
}

//Usage
#{class-begins-with(main-toolbar-action)}{
    color: black;
}

//Output
[class^="main-toolbar-action"], [class*=" main-toolbar-action"] {
    color: black;
}

//Matches
<button class="whatever main-toolbar-action--details">Details</button>
<button class="main-toolbar-action--upload whatever">Upload</button>
<button class="whatever main-toolbar-action--new-folder whatever2">Create New Folder</button>

//Or even...
<button class="main-toolbar-action">Generic Action</button>