Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v0.7.0)
// ----

//interpolation bug in libsass example

$one: one;
$two: two;

.variabubble {
  background: url(#{$one}-#{$two}.png);
  // seems ok in property or value, but just not inside () ?
  property-#{one}-#{two}: output;
  property: output-#{one}-#{two};
  background: #{$one}-#{$two}; // without ()
//  background: #{$one}-#{$two}.png; // this fails when I add the 'dot'
  }

.variabubble2 {
  //contains no dash character, that is trying to do math?
  background: url(#{$one}#{$two}.png);
  }

.variabubble3 {
  //weirdly though, / is ok, although + and * aren't
  background: url(#{$one}/#{$two}.png);
  }

SassMeister-output.css

.variabubble {
  background: url(#{$one}-#{$two}.png);
  property-one-two: output;
  property: output-one-two;
  background: one-two; }

.variabubble2 {
  background: url(onetwo.png); }

.variabubble3 {
  background: url(one/two.png); }