lexer puzzle

Keith Wansbrough Keith.Wansbrough at cl.cam.ac.uk
Fri Sep 26 12:08:27 EDT 2003


> > Hi.  I'm really new to Haskell, just learning it, and I must say I'm pretty
> > overwhelmed by the large variety of constructs. (=>, <-, \ to name a few)
> 
> Would that be \ as in TREX row variable polymorphism? Just remember most
> operators are just library functions. It's only =, ->, =>, <-, :: that are
> really part of the language, and {,},; for grouping. Did I miss any?

Yes, you missed \, which is used for function abstraction:

(\x -> x*x) 3

And ( , ) for tuples.

And I don't think "->" is part of the language - it only appears in the type syntax, not term syntax.  If you allow it, you have to allow * as well.

--KW 8-)
-- 
Keith Wansbrough <kw217 at cl.cam.ac.uk>
http://www.cl.cam.ac.uk/users/kw217/
University of Cambridge Computer Laboratory.



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