Sass Calc

Easily build complex calc() expressions in Sass. Leverage calc() to do math that Sass can't.

Use add(), subtract(), multiply() and divide() on values which have incompatible or unknown units, or which are var() expressions, or which are calc() expressions themselves. Return a new calc() expression, or use straight math where possible.

# in your project
npm install --save @lunelson/sass-calc

// in your sass file, assuming you have 'node_modules' in Sass' search path
@import '@lunelson/sass-calc/index';

// test.scss
:root {
  --foo: 20px;
}
$expr: calc(100vw - 50%);
.test {
  test: subtract(1.5em, 1em);
  test: add(1.5em, 1rem);
  test: add(multiply($expr, 2), 10px);
  test: add(multiply(var(--foo), 2), 10px);
  test: divide(subtract(1.5em, 1em), 2);
  test: subtract(divide(subtract(1.5em, 1em), 2), add(1em, 1ex));
}

/* test.css */
:root {
  --foo: 20px;
}

.test {
  test: 0.5em;
  test: calc(1.5em + 1rem);
  test: calc(((100vw - 50%) * 2) + 10px);
  test: calc((var(--foo) * 2) + 10px);
  test: 0.25em;
  test: calc(0.25em - (1em + 1ex));
}

Refs:

• https://www.sitepoint.com/sass-basics-operators/
• https://www.sitepoint.com/understanding-sass-units/
• http://caniuse.com/#feat=calc

Questions? Twitter me.