On 02/27/10 14:39, Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> I think c ! 2 is the third element of c, not unlike c[2].
> 
>   [] is used almost universally for indexing in most languages (not only
> for random access of arrays, but also eg. accessing relational sets (where
> the thing inside the square brackets is the key and the return value is the
> data)). Is there a logical reason why Haskell chooses an odd syntax of
> "x ! y" for the same thing than most other languages express as "x[y]"?
> 
>   Using ! for the nth element is not very expressive. In mathematics ! is
> usually used for factorials, in many programming languages it's used to
> express logical negation (granted, not a very logical choice per se, but
> quite established), and in natural languages it's used to express shouting
> or to emphasize the importance of something (like "WARNING!").
> 
>   So why choose ! as "the nth element"? Did they run out of obfuscated
> one-character operators and it was the only one left? Or is there a logical
> reason to choose that symbol out of all possible that I'm not aware of?
> (Well, I wouldn't actually be surprised if that symbol had been used for
> that purpose in some weird mathematical notations eg. in some lambda
> calculus or the like since the 1930's or such.)
> 
>   I know Haskells undying love for obfuscating brevity, but would it have
> hurt to actually use a descriptive *name* for that function? I don't know,
> like "c element_at 2" (or even "c at 2") or whatever.

	Now you know how lots of people feel when they have to learn UNIX
(command line). At some point, you just tell them, "Hey, that's the way
it is. Weird, obscure, but works, and doesn't really get in your way
once you know it".

-- 
Depend on the rabbit's foot if you will, but remember, it didn't help
the rabbit.

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