From: Peter Zotov <whitequark@...>
Date: 2011-10-31T14:45:56+09:00
Subject: Re: How to save method signature while wrapping it?

Alexey Petrushin писал 30.10.2011 22:42:
> Hello, it would be interesting to automatically destruct hashes into
> named method arguments, Ruby has the Method.parameters method:
>
>     class A
>       def my_method a, b, c = 10; end
>       p instance_method(:my_method).parameters
>       # ==> [[:req, :a], [:req, :b], [:opt, :c]]
>     end
>
> (snip)
>
> So, I'm wondering, maybe there's some way to wrap method and still
> preserve its signature?
>
> Basically attribute names are available (from method.parameters), but 
> I
> don't know how to express named attributes in
> block signature, i.e. - how to dynamically write `... do |args[1],
> args[2], args[3]|` instead of `... do |*args|` (without eval of 
> course
> :) ).

I'd say that in this case `eval' is fine: the environment is 
controlled, and
the code being generated is very deterministic. On any sane 
implementstion, after
the parsing step this code will be absolutely equivalent to 
"properly"-defined one,
and the parsing delay is negligible.

-- 
   WBR, Peter Zotov.