Odd error message for `runghc` with missing `main` function.

[isaacdupree]

% cat what.hs
module Main where {}

% runghc what.hs
what.hs:1:33:
    Not in scope: `main'
    Perhaps you meant `min' (imported from Prelude)

'ghc what.hs' gives a rather more sensible message.

[simonpj]

Nothing to do with runghc really; its the -e mode:

ghc -e wombat what.hs
<interactive>:1:1: Not in scope: ‛womab’

But really it should say

what.hs:1:33:
    Not in scope: `main'
    Perhaps you meant `min' (imported from Prelude)

I'm not sure where the -e processing happens, and couldn't find it with a quick look. Ian, you've been refactoring the pipeline recently, might you look?

Simon

[igloo]

I'm confused - doesn't it already say that?

[simonpj]

Oh, sorry, I meant that it should say

what.hs:1:1: The function `main' is not defined in module `Main'

If instead it was

module What2 where
foo = True

and you said

ght -e bar What2.hs

then a "not in scope" message would make more sense. But in the common case of 'main' (which is what happens with runghc), the No main in Main message is better

Simon