From: Daniel Schierbeck <daniel.schierbeck@...>
Date: 2006-08-18T04:45:13+09:00
Subject: Re: Multiple arguments for Hash#delete

Trans wrote:
>> If #delete should be altered, why should #[] and #[]= ?
> 
> You may have a point. Though it doesn't matter as much becuase it's
> much less often the anyone depends on the return value of []=. ie. we
> just use it to set values. 

I only added #[]= because, with Facets, you can do this (as you of 
course know)

   hsh[:a, :b, :c] = 1, 2, 3

which matches nicely with

   a, b, c = hsh[:a, :b, :c]

My point is that #delete is also a retrieval method, in the sense that 
it returns the value it has removed from the hash. Therefore it is 
natural for it to have the same functionality as #[], which in turn 
means that we have to alter #delete in Facets.

   a, b, c = hsh.delete(:a, :b, :c)

Simple and elegant.

> But to be very percise it should probably be
> changed to match Array's. Consider that Array's []= method does take
> multuiple parameters related to slicing. Facets' deals with that by
> allowing it to also take an  Array parameter:
> 
>   a = []
>   a[[1,2,3]] = :a, :b, :c
>   a #=> [ :a, :b, :c ]
> 
> Hash's can be made to do the same. What do you think?

Actually, I don't like that solution very much. It doesn't seem very 
elegant.


Cheers,
Daniel