/// @param {String} $size-name - Get a recommended space size by name.
/// @return {Number} - A px value (or rem value if relative units have been enabled).
@function oSpacingByName($size-name) {
	$value: map-get($_o-spacing-sizes, $size-name);
	@if(type-of($value) != 'number') {
		@error 'There is no recommended space named "#{$size-name}". Should be one of #{map-keys($_o-spacing-sizes)}.';
	}
	@return oSpacingByIncrement($value);
}

/// @param {Number} $increment - The number to multiply the baseline size by.
/// @return {Number} - A px value (or rem value if relative units have been enabled).
@function oSpacingByIncrement($increment) {
	@if(type-of($increment) != 'number' and floor($increment) != $increment) {
		@error 'Expected a whole number but was given "#{$increment}".';
	}
	@return $increment * oSpacingGetBaselineValue();
}

/// @return {Number} - A px value representing our spacing baseline (or rem value if relative units have been enabled).
@function oSpacingGetBaselineValue() {
	@if($o-spacing-relative-units) {
		@return div($_o-spacing-baseline, 16) * 1rem;
	}
	@return $_o-spacing-baseline * 1px;
}