Re: [Haskell-cafe] map (-2) [1..5]

David House wrote:

On 17/08/06, Brian Hulley wrote:

...

Literal highlighting in the editor would make it clear that x-2 === x (-2). I think a basic issue is that at the moment it is strange that non-negative numbers can be specified as literals but negative numbers can't - they can only get in through the "back door" of evaluation - which just doesn't seem right.

You also can't specify string literals: they're sugar for 'a':'b':'c':[]. You seem to be arguing that syntactic sugar, and by extension, a small core language, is bad.

All I'm saying is that given a type, either all the inhabitants should have a literal form or none of them should, because otherwise the availability of literals skews one's relationship to the inhabitants. Ie the lack of negative literals tells me that I should think of negative integers as being "derived" from positive integers via negation, whereas the declaration data Integer = ... | -1 | 0 | 1 | ... tells me that the negative and positive integers are on an equal footing. Ie the language is sending out a "mixed message" about the integers, which is confusing. Regards, Brian. -- Logic empowers us and Love gives us purpose. Yet still phantoms restless for eras long past, congealed in the present in unthought forms, strive mightily unseen to destroy us. http://www.metamilk.com