[Haskell-cafe] Re: Who is afraid of arrows,
was Re: ANNOUNCE: Haskell XML Toolbox Version 9.0.0
apfelmus at quantentunnel.de
Wed Oct 13 03:50:53 EDT 2010
David Virebayre wrote:
> Gregory Crosswhite wrote:
>> Also, I don't see why one would prefer >>> over the standard function
>> composition operator, ".".
> With "." you have to read right-to-left to follow data's path.
> For me that reading order isn't natural, and I imagine it is so for
> most people which don't have a mathematical background.
> Combined with >>= / >> you have multiple reading direction in the same
> expression, as in
> expression ( c . b . a ) `liftM` a1 >>= a2 >>= a3
> reading order 6 5 4 1 2 3
> So that could be one reason.
That's why I'm usually using =<< instead of >>= .
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