Hey guys,

our theme uses the index function for sass lists. While upgrading to ExtJS 6.5.3.57 and Cmd 6.5.3.6 the following error occurs when building the theme with sencha app build:
Code:
Fashion Error : Failed to find method for operation - on type number with value 1.
First of all this error message is not all to helpful but nevertheless I found the error on this line:
Code:
$index: index($color-names, $color) - 1;
The index function is not found, therefore it is treated as a string and minus 1 does throw the error.

Seems that Fashion has not implemented the index function for lists? Is that so, and if yes shouldn't this be included?

For anyone running into this error the easy way out is to implement the index function:
Code:
@function index($list, $value) {
    @for $i from 1 through length($list) {
        @if nth($list, $i) == $value {
            @return $i;
        }
    }
    @return null;
}