From: "Mauricio Fernández" <batsman.geo@...>
Date: 2002-11-27T04:26:31+09:00
Subject: Re: Default value of property

On Tue, Nov 26, 2002 at 10:44:50AM +0900, ahoward wrote:
> On Tue, 26 Nov 2002, Tim Bates wrote:
> 
> [snip]
> T> if object.property
> T> 	object.property.method
> T> else
> T> 	default_value
> T> end
> [snip]
> 
> how about
> 
>   object.property and object.property.method or default_value
> 
> you could do something like
> 
>   object.property.method rescue default_value
> 
> but this does not catch NameError, unless someone else knows the syntax for
> this?

What's wrong about '? :' ?

irb(main):001:0> b = nil
nil
irb(main):002:0> (__f=b)?__f.meth : nil
nil
irb(main):003:0> class A
irb(main):004:1> def meth
irb(main):005:2> puts "AAAA"
irb(main):006:2> end
irb(main):007:1> end
nil
irb(main):008:0> b = A.new
#<A:0x4026d994>
irb(main):009:0> (__f=b)?__f.meth : nil
AAAA
nil
 
OK, we pollute the local variable name-space w/ __foo, but would anybody
_really_ want to use that one?

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