[Haskell-cafe] Re: let and fixed point operator
peter at syncad.com
Mon Sep 3 09:54:08 EDT 2007
Jules Bean wrote:
> I have no idea what you're talking about. It works fine on multiple lines:
> f x = g
> . transform displacement
> . scale factor
> $ x
> is perfectly valid.
Yes, it is. It is not an issue if you prefer to indent based on previous line
instead of "always by the same small amount of spaces". And then problem
happens when the amount of spaces is less than 5. E.g. this does not work:
h x = x
f x =
let g x =
(+ 5) .
(* 2) $
I do not like to indent based on previous lines since it should be re-indented
when the previous lines change (e.g. because of identifier rename). So I indent
based on previous lines only when it adds a LOT to readability. Of course
fixed amount indentation by big enough number of spaces would do but then your
code gets too wide if more blocks are nested and I like to be withing 110 chars
at worst (preferably 80).
This is probably not a problem for "where" keyword then the next longest from
the "let", "where", "do", "of" set is "let" which would mean that 5 should be
enough, not that bad, but looks much for me. Other option is to leave "let"
keyword alone on the line and then indent "g x" by one and the function body
by two indentation units from the "let" keyword.
So from my point of view the point free style is great if it fits on one line
well ... otherwise it depends.
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