[Haskell-cafe] minor refactoring problem

[Stefan Holdermans]

Martin,

> Quick question: what's the difference between
> 
> importFile ed = readfile >=> fromRawFile >=> setEditor ed
> 
> and
> 
> importFile = readfile >=> fromRawFile >=> setEditor
> 
> that the former compiles but the latter doesn't?

Note that, in Haskell, function application has higher priority then any other infix operation. So,

  importFile ed = readfile >=> fromRawFile >=> setEditor ed

is the same as

  importFile ed = readfile >=> fromRawFile >=> (setEditor ed)

If you write

  importFile = readfile >=> fromRawFile >=> setEditor

then this is (via eta expansion) more or less equivalent to

  importFile ed = (readfile >=> fromRawFile >=> setEditor) ed

which is clearly not the same as the original definition.

HTH,

  Stefan