Variables not working in calc?

Question

Sass

I came across this miracle:

$one    : 1170px;
$two   : 500px;
$three : calc($one - $two);

At the output, I get such an expression, that is, the variables are not converted to numbers. There are no errors in the console.

Answer 1

calc(#{$one} - #{$two});
https://github.com/sass/sass/issues/818