=mixme
  color: blue

input
  +mixme
  background: red

=apply-to-ie6-only
  * html
    @content

+apply-to-ie6-only
  #logo
    background-image: url(/logo.gif)

@mixin inc()
  mix: in

.a
  +
    .c, .b
      margin: 10px
      +inc

.a
  +inc
  + b
    .c, .b
      margin: 10px


.a
  >
    .c, .b
      margin: 10px