SCSS代码：

 @each $header, $size in (h1: 2em, h2: 1.5em, h3: 1.2em) {
  #{$header} {
    font-size: $size;
  }
}

 reg@Express:~/workspace$ sass style.scss:style.css
Syntax error: Invalid CSS after "@each $header": expected "in", was ", $size in (h1:..."
        on line 1 of style.scss
  Use --trace for backtrace.
reg@Express:~/workspace$

sass版本是 Sass 3.2.12 (Media Mark) ,ruby版本ruby 1.9.3p484 (2013-11-22 revision 43786) [x86_64-linux]