[Haskell-cafe] Re: [Haskell-beginners] map question

wren ng thornton wren at freegeek.org
Mon Oct 19 00:09:31 EDT 2009

Will Ness wrote:
> Luke Palmer <lrpalmer <at> gmail.com> writes:
>> Or you could use the "subtract" function.
>>   >>> map (subtract 2) [3,4,5]
>>   [1,2,3]
> I don't want to.
>> I don't think syntax sugar is worth it in this case.
> I do. Operators are great because they make our intent visible, immediately 
> apparent. Long words' meaning, like subtract's, is not immediately apparent, 
> and they break consistency. Not everyone's first language in life was English, 
> you see.

I'm with Luke on this one. It's a shame that negation uses the same 
symbolic identifier as subtraction, but introducing this new sugar only 
serves to make things more complex than they already are. If anything, 
negation should be moved to using a different identifier to remove the 
current ambiguity (as is done in some other languages).

> (`foldl`2) works.
> (`-`2) should too.

The `` syntax is for converting lexical identifiers into infix 
operators. Symbolic identifiers are already infix, which is why `` 
doesn't work for them. If we introduced this then those striving for 
consistency would be right in requesting that this pattern be allowed 
for all symbolic operators. I for one am opposed to introducing 
superfluous syntax for duplicating the current ability to write things 
in the same ways.

Attack the underlying problem, don't introduce hacks to cover up broken 
hacks. This isn't C++.

Live well,

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