From: "Gonzalo Garramuño" <ggarra@...>
Date: 2007-12-24T12:54:29+09:00
Subject: Re: 1.9 problem with function *args parameters.

Yukihiro Matsumoto wrote:
> 
> Try explicit hash like:
> 
>>    FileUtils.cp_r(src, dest, {:verbose => true}, *opts) rescue nil
> 
> 1.9 only allows hash without braces at the very last of the
> arguments. 
> 

I thought I was doing that, but it is clearly not what the parser thinks 
(neither in 1.8 or 1.9).  I was expecting that just splatting the 
arguments would then consider all the last arguments as a flattened 
array and thus a (merged) hash.

Thus, the issue is more than a syntax problem, but a logic one.  Sadly, 
the only way to achieve the behavior I am looking for is really still 
this ugly stuff.

def cp_r( src, dst, opts = {} )
   FileUtils.cp_r( 'src', 'dst', { :verbose => true }.merge(opts) ) rescue
end

Which is yucky and slow as the merge is done explicit instead of 
implicit by the interpreter.

I'm thinking this maybe this should be a feature request.

To have some simple syntax like:

def cp_r( src, dst, *opts )
   FileUtils.cp_r( 'src', 'dst', :verbose => true, *opts )
end

to be interpreted as a single merged hash at the end.

Perhaps the splat operator is not the best syntax or operator, thou.

I think the idiom of needing merging hashes as parameters are passed is 
way too common to deserve some syntax.


-- 
Gonzalo Garramu�o
ggarra@advancedsl.com.ar

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