G'day rsFalse,

A couple of tips from someone who's fallen foul of both the problems you've encountered on more than one occasion:

1. Whenever I get a "Use of "whatever" without parentheses is ambiguous" warning, adding the parentheses, rather than casting around for some other workaround, is generally the easiest solution.
2. Quotes within one-liners are problematic. Consider using the various q{}, qq{}, etc. Quote-Like Operators instead of literal quotation marks.