21 Nov
2007
21 Nov
'07
10:31 a.m.
Am Mittwoch, 21. November 2007 15:03 schrieb Serge D. Mechveliani:
Dear GHC developers,
when compiling the function f x = if x them False else True
ghc-8.8.1 reports: " parse error on input `else' ".
When there is a large expession after `them', it is sometimes difficult to locate a typo. Why does not it report " parsing if-then-else: cannot find `then' " ?
Regards,
them is a perfect identifier. So probably x them False gets parsed as an expression (x applied to them and the result applied to False). Haskell’s lightweight syntax makes programs short and easy to read (in my opinion) but it often makes the compiler unable to guess where your mistake lies. Best wishes, Wolfgang