Generated by SassMeister.com.

SassMeister-input.sass

// ----
// Sass (v3.3.0.rc.1)
// Compass (v0.13.alpha.7)
// ----

$magic-number: 24px
$size: 31px

@function calculateEm($target, $context: $magic-number) 
	$emSize: 0
	@if $target == 0
		@return $emSize
	@if $target > $context
		@if $target < ($context * 2)
			$emSize: ($context * 2) / $target
		@else if $target < ($context * 3)
			$emSize: ($context * 3) / $target
	@else
		$emSize: $context / $target

	@return $emSize + 0em
	
test
	value: calculateEm($size)
	type-value: type-of(calculateEm($size))
	type-test-1: type-of(1.54839em)
	
	test-1: calculateEm($size) == 1.54839em
	test-2: calculateEm($size) == calculateEm($size)
	

SassMeister-output.css

test {
  value: 1.54839em;
  type-value: number;
  type-test-1: number;
  test-1: false;
  test-2: true;
}