Local "open", or open locally

Local "open", or open locally

[Lukasz Stafiniak]

Dear list,

What about a construct for opening modules locally in an expression? For example

module SomeModule = struct let x = 5 end
module SomeOtherModule = struct let y = 7 end

let z = open SomeModule and SomeOtherModule in x + y + x*y

It can currently be expressed as:

let z = module XY = struct open SomeModule open SomeOtherModule
  let z = x + y + x*y end in XY.z

Perhaps it could be considered as a language extension. It seems nice
as it "catches the focus". (I'm going to use it with Camlp4 but it
seems uglier that way.)

I wouldn't buy it for my kidney, though. ;)

Best Regards,
Lukasz Stafiniak

Re: [Caml-list] Local "open", or open locally

[Richard Jones]

On Mon, Aug 01, 2005 at 03:47:43AM +0200, Lukasz Stafiniak wrote:
> let z = open SomeModule and SomeOtherModule in x + y + x*y

Yes, I too would really like this syntax in the core language, as well
as local type and exception definitions.

There is a camlp4 extension for local open, called openin:

http://www.eleves.ens.fr/home/frisch/soft.html#openin

Rich.

-- 
Richard Jones, CTO Merjis Ltd.
Merjis - web marketing and technology - http://merjis.com
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Re: [Caml-list] Local "open", or open locally

[Lukasz Stafiniak]

> There is a camlp4 extension for local open, called openin:
> 
> http://www.eleves.ens.fr/home/frisch/soft.html#openin
> 
Thanks. I've extended it with lists of modules, and reworked tuareg.el
quickly (but to make it simpler I removed "open" from phrase
delimiters). It works fine :)