<===> options.yml
---
:todo:
- libsass

<===> input.scss
$x: ground;
$y: e;
$z: it;

div {
  back#{$x}: {
    imag#{$y}: url(foo.png);
    pos#{$z}ion: 50%;
  }
}

span {
  background: {
    image: url(bar.png);
    position: 100%;
  }
}

p {
  border: {
    upper: {
      left: 2px;
      right: 3px;
    }
  }
}

@warn 2 + 3;

/* 2 + 3 */
/* #{2 + 3} */

foo|div {
  color: red;
}

$-hey : hey;

div sp\ ,#abcan {
  color: red;
  p, |q {
    background: blue;
    color: \hey;
    width: \10 + \20 \ ;
    a {
      height: 1;
    }
  }
}

d\ v, sp\ n {
  a {
    color: blue;
  }
}
<===> output.css
div {
  background-image: url(foo.png);
  background-position: 50%;
}

span {
  background-image: url(bar.png);
  background-position: 100%;
}

p {
  border-upper-left: 2px;
  border-upper-right: 3px;
}

/* 2 + 3 */
/* 5 */
foo|div {
  color: red;
}

div sp\ , #abcan {
  color: red;
}
div sp\  p, div sp\  |q, #abcan p, #abcan |q {
  background: blue;
  color: hey;
  width: \10 \ \ ;
}
div sp\  p a, div sp\  |q a, #abcan p a, #abcan |q a {
  height: 1;
}

d\ v a, sp\ n a {
  color: blue;
}

<===> warning
WARNING: 5
         on line 28 of input.scss

<===> warning-dart-sass
WARNING: 5
    input.scss 28:1  root stylesheet