Re: Avoid blank line separating code and comments in Bird style?

At Wed, 14 Jan 2015 10:55:41 -0500, Richard Eisenberg wrote:

I think the underlying problem here is that there is a difference between "literate" comments and "normal" comments.

In a bird-style literate Haskell file, this is what I'll call a literate comment:

~~~ A line with no marker at the beginning ~~~

A normal comment is in a line of Haskell code, put with a comment indicator:

~~~

...

-- This is a "normal" comment

When GHC sees a bird-style literate Haskell file, it first strips out all lines that don't begin with >. Then, it starts doing its real work, including parsing Haddock comments. So, to use a Haddock comment in a literate Haskell file, you'd need to use the "normal" comment style:

...

-- | Make a numbered widget mkWidget :: Int -> Widget

There is no way to use Haddock markup in a "literate" comment.

But, as Mateusz points out, there may be blank lines between the Haddock comment and the thing being described:

...

-- | Get the number of a widget

widgetNum :: Widget -> Int

I understand and agree with all you say above...

I hope this clarifies things!

...but unfortunately it doesn't solve my problem. I guess my attempt to motivate with the Haddock use case confused things. What I want to do has nothing to do with Haddock. All I would like is, very simply (in Bird style) literate comment and code next to each other with No Intervening Blank Lines separating them. But GHC doesn't accept this and GHC reports the error 'unlit: Program line next to comment'. If I add a blank line between the literate comment and code, GHC accepts it. Summarizing, following is accepted by GHC without error (notice blank line separating literate comment and code): literate comment

haskell code

For following GHC reports error, but it is what I require: literate comment

code

So. Is there any way GHC can be coaxed to accept a Bird style literal Haskell file with no blank line separating code and literal comment?

Richard

Sidhu

On Jan 14, 2015, at 2:42 AM, sidhu1f wrote:

...

At Wed, 14 Jan 2015 12:31:54 +0530, Mateusz Kowalczyk wrote:

...

I imagine you're suggesting that something like

...

Literate comment

...

someCode = undefined

This (literate comment followed by code with no intervening blank line) is exactly what I want (regret my explanation was unclear). But when I try it, GHC reports the error 'unlit: Program line next to comment'.

...

is allowed ...

As you mention above behaviour is allowed, could you let me know how to enable it?

Regards Sidhu _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users