space separated values interpreted as list...

I’m trying to write a function that takes a comma separated list of box-shadows and converts them to filter: drop-shadow.

I’m having a problem, if I pass a single shadow to my function, Stylus interprets it as an array instead of a string, and then it get parsed by the for loop.

drop-shadow($array...)
  $dropShadows = ()

  for $shadow in $array
    push($dropShadows, 'drop-shadow(' + $shadow + ')');

  filter: unquote(join(' ', $dropShadows))

drop-shadow: 0 0

$array is of type unit, but the result is:

filter: drop-shadow(0) drop-shadow(0)

Why?

[Panya]

Actually 0 0 is a list from the Stylus perspective. If I understand your problem correctly, you can use list-separator bif to check if the given list is separated by comma:

drop-shadow()
  if list-separator(arguments) == ','
    $dropShadows = ()
    for $shadow in arguments
      push($dropShadows, 'drop-shadow(' + $shadow + ')');
    filter: unquote(join(' ', $dropShadows))
  else
    filter: arguments

[FezVrasta]

Opened a dedicated bug for it https://github.com/stylus/stylus/issues/2196