@BLOCK

You can assign any block of code in Stylus to a variable and then call it, pass as an argument or reuse in any other way.

To define a block, either write it down with an increased indent after an assign sign:

foo =
  width: 20px
  height: 20px

or use a curly braces syntax with @block keyword:

foo = @block {
  width: 20px
  height: 20px
}

if you would like to render this block anywhere, you could call this variable inside an interpolation, so

.icon
  {foo}

would render to

.icon {
  width: 20px;
  height: 20px;
}

BTW, this is the same way you can use the blocks passed to the block mixins.

Right now you can only pass the variable as any other variable and render it inside an interpolation. In future we would provide more ways of handling it.