From: Mait <mattengi@...>
Date: 2006-10-19T13:50:11+09:00
Subject: Re: My first feeling of Ruby

Florent Guiliani 작성:

> [] for reading:
> irb(main):152:0> hash["A"]
> => 1
>
> If you go wrong:
> irb(main):156:0> hash{"A"}
> => 537984250
> irb(main):154:0> hash = [ "A"=>1 , "B"=>2 ]
> => [{"A"=>1, "B"=>2}]
>
> I would prefer an error or warning. The last line means I can omit {}?

Yes, you can omit {} for method argument in some condition.

hash = [ "A"=>1 , "B"=>2 ]
hash = Array.new << {"A"=>1 , "B"=>2}
hash = Array.new.push("A"=>1, "B"=>2)

Third form is regular. Think first and second case is special thing.

quote in PickAxe book(Programming Ruby):

>Collecting Hash Arguments

>...snip

>You can place key => value pairs in an argument list, as
>long as they follow any normal arguments and precede any array and block arguments.
>All these pairs will be collected into a single hash and passed as one argument to the
>method.

I think this feature make method call interface more freely.

method_call :one => something
method_call :two => another
method_call :one => something, :two => another
method_call :two => another, :one => something, :three => this