From: Jarmo Pertman <jarmo.p@...>
Date: 2010-06-16T23:01:07+09:00
Subject: strange behaviour if exploding parameters

Hello!

I've just happened to find strange behaviour when trying to explode
parameters.

Why doesn't it work?
irb(main):007:0> lambda {|*parameters| *parameters.class}
SyntaxError: compile error
(irb):7: syntax error, unexpected '}', expecting tCOLON2 or '[' or '.'
        from (irb):7
        from :0


class is Array if 0 or more parameters given
irb(main):009:0> l = lambda {|*parameters| p *parameters.class}
=> #<Proc:0x04b7e510@(irb):9>
irb(main):010:0> l[]
Array
=> nil


class is Array if some parameters given
irb(main):012:0> l = lambda {|*parameters| x = *parameters; p x.class}
=> #<Proc:0x04b2c880@(irb):12>
irb(main):013:0> l[1,2]
Array
=> nil


class is NilClass instead of Array?
irb(main):014:0> l[]
NilClass
=> nil

Any ideas why class is NilClass instead of Array if *parameters is
assigned to local variable? I'd expect it to be always an Array and if
no parameters given then an empty Array.

Best Regards,
Jarmo
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