Re: lambda, ->, haskell, and so on

Hi --

On Tue, 6 May 2008, ts wrote:

> David A. Black wrote:
>>    define_method(:m) &lambda(x,y,z) { block }
>
> too complex for me :-)

For some reason I doubt it :-)

>>
>> I thought that was one of the purposes of ->(){} -- to let you use
>> method argument semantics in Proc objects. Am I wrong about that?
>
> no, probably.
>
> This is just me which associate, probably wrongly, lambda and
> define_method and 1.9 seems have method argument semantics with
> lambda

I don't think so -- only ->(){}:

$ /usr/local/lib/ruby-trunk/bin/ruby -ve 'lambda {|a=1|}'
ruby 1.9.0 (2008-04-30 revision 16244) [i686-darwin9.2.2]
-e:1: syntax error, unexpected '=', expecting '|'
lambda {|a=1|}
            ^
$ /usr/local/lib/ruby-trunk/bin/ruby -e '->(a=1){}'
$

I think that's why Paul is suggesting lambda(args) {}, where args
could be any method-style argument list.


David

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