SASS mixin error because of Deprecation - sass

Question

I am using the following mixin for REM conversions
https://gist.github.com/bitmanic/1134548
Since the latest SASS update the mixin is now showing an error:
// If the value is zero or a string or a color, return unchanged input
#if $value == 0 or type-of($value) == "string" or type-of($value) == "color" {
$rem-values: append($rem-values, $value); }
#else {
$rem-values: append($rem-values, $value / $baseline-rem); } }
The result of 0px == 0 will be false in future releases of Sass. Unitless numbers will no longer be equal to the same numbers with units.
I am a bit new to SASS, can someone help trouble shoot this?

Answer 1

Are you sure it's an actual error rather than a warning?
The warning is likely in reference to this issue. The jist of the problem being fixed here is where 1px == 1, which is inherently untrue.
Realistically, you should always use 0 for lengths rather than 0px, despite the fact that they are equal, simply because you would be saving a few bytes. You should be able to strip off the unit and then perform the comparison:
$baseline_px: 10px;
#mixin rem($property, $px_values) {
// Convert the baseline into rems
$baseline_rem: ($baseline_px / 1rem);
// Print the first line in pixel values
#{$property}: $px_values;
// Create an empty list that we can dump values into
$rem_values: ();
#each $value in $px_values {
// If the value is zero, return 0
#if $value / ($value * 0 + 1) {
$rem_values: append($rem_values, $value);
zero: $value;
}
// If the value is not zero, convert it from px to rem
#else {
$rem_values: append($rem_values, ($value / $baseline_rem) );
not-zero: $value
}
}
// Return the property and its list of converted values
#{$property}: $rem_values;
}
.foo {
#include rem(font-size, 10px);
#include rem(border-width, 0px);
#include rem(border-width, 0);
}
Alternately, you could check if it is within a list of zero values:
#if index((0, 0px), $value) {
// do 0 related stuff
}