Make coercion if #=== operator doesn't know what to do
Related to http://bugs.ruby-lang.org/issues/7604
It'd be fine if === will do coerce when it doesn't know what to do. In ticket above I gave use-case for case-statement which needs that any ruby object could be coerced to a "pattern".
when ['several', 'words'] then puts 'arr have last two elements: several, words'
when ['word'] then puts 'arr have last element: word'
else puts 'cannot understand'
It'd be possible if Array#===(predicate) will simply use usual coerce call: predicate.coerce(arr) -- Predicate#coerce is a good point to understand behavior of such matching.
def initalize(string); @string = string; end
if other.is_a? Regexp
when /pat/ then 'it works'
Here we shouldn't monkeypatch Regexp class and it's good, we can make an error only in our own class MyString.
Updated by matz (Yukihiro Matsumoto) almost 9 years ago
- Status changed from Assigned to Rejected
Objects except for numbers does not have coerce protocol. I am not sure how far OP wants to dig in.
Design and implement coerce protocol? Or special kind of coercion for case statement?
In that sense, this proposal is half-baked.
Re-submit if you come up with concrete behavior definition, e.g. what "doesn't know" mean.