From: Jakub Travnik <j.travnik@...>
Date: 2001-11-25T23:44:30+09:00
Subject: [ruby-talk:26450] Re: ++operator and sorted hashes

Willi Kappler wrote:

> Hi list,
> 
> I'm new to ruby ( using 1.6.5 ) and comming from c++. The language is really great
> and easy to learn. But there are some things that would be fine
> if they were implemented:
> 
> Is there a certain reason why the ++operator is not implemented ?
> In c/c++: a=5; a++;
> In ruby: a=5; a+=1


In Ruby everthing is object,
a++ means add one in C.
What this should mean for String? for Regexp? for Your own class?
It does not have usefull object semantic.

However a+=something is ok:
a=10;a+=1

a='Hello'; a+=' world'

a=MyClass.new; a+=MyClass.new
(if MyClass have instance method + defined)

 
> An other really usefull object is hash ( map in c++ stl )
> In c++ maps are sorted, in ruby there is a sort function, but it
> returns an array. I thought that c++ uses sorted maps for speedup
> reasons, so there must be an other reason why ruby doesn't sort them ?


It is a implementation reason.
there are some links that might explain more about hash tables:
http://www.nist.gov/dads/HTML/hashtab.html
http://www.wikipedia.com/wiki/Hash_table


Jakub Travnik
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