From: "David A. Black" <dblack@...>
Date: 2009-11-01T02:08:00+09:00
Subject: Re: In-place parameter modification

Hi --

On Sun, 1 Nov 2009, Dave Anderson wrote:

> 7stud -- wrote:
>> Judson Lester wrote:
>>> Finally: ruby is a pass-by-reference language, so if you actually do
>>> make
>>> changes the parameters of a method, the callers variables will change as
>>> well.
>>
>> def test(x)
>>   x = 10
>> end
>>
>> num = 5
>> test num
>> puts num
>>
>> --output:--
>> 5
>>
>> ???
>
> My educated guess is that string.replace("Chunky bacon") is operating on
> the original, whereas string = "Chunky bacon" just makes a new local
> copy. The pickaxe book suggests that this only works on Arrays, Hashes
> and Strings, though, so there's no way to make replace work on a fixnum.

That's a good thing :-)


David

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