Hi Manuel, Everybody, I am just getting into LuaLaTeX. I needed to do some work with MetaPost. While working I came across a kudo. That is once inside the mblibcode environment one can not call Lua. THIS I consider a missing feature and a VERY important one. I figured it should not be not hard to add in this functionality, Which as it seems it is not. I look into the luamplib manual and notice that all that was needed was to patch luamplib.addline. All that was needed was to create a syntax/command that was inside the MetaPost code noticed this command extract the function call and have it executed. I have done this. It is just a couple of lines of code. On the TeX of LuaLaTeX side, one can know write \begin{mplibcode} <some normal Metapost commands> mplibcodedolua(<Lua function call>) <more Metapost commands> \end{mplibcode} My questions are: 1) Is there any interest in such a function. As I mentionedabove this is not a Lua function, just syntatic sugar so that the provide Lua function gets called. 2) What should it be called. mblibcodedolua ? I am asking this before I present my code here so that my code presents a rounded picture. regards Keith.
On 7-8-2012 09:29, Keith J. Schultz wrote:
Hi Manuel, Everybody,
I am just getting into LuaLaTeX.
I needed to do some work with MetaPost.
While working I came across a kudo. That is once inside the mblibcode environment one can not call Lua. THIS I consider a missing feature and a VERY important one.
Some (simple) support for lua calls is on the (long term) agenda but not before the current mplib extensions project is done (i.e. the decimal calculation plugins). Calling lua in itself is not so much an issue; after all one can just do a \directlua inside a blob of mp passed to mplib (I do that all the time). For an lua 'primitive' in mplib (which then probably would just be called just 'lua') we first need to figure out: 1 - how to access mp internals (and that relates to the mentioned decimal extensions, as we might need to get and set) 2 - if and how we can share the state with the (main) tex lua instance 3 - how we want to print back to mp (like tex.[s]print) It's one of those feature we have discussed (maybe too) long ago, but because it has to be more than just (3) it never ended up first on the todo list (first finishing the main lib). The problem with these things is that it has to be mostly 'right from the start' in order not to conflict too much with long term usage). Anyhow, if you play with such things, best have something lua "mp.print(123)" Given mp's somewhat different parsing and expansion compared to tex there are also some conceptual issues involved. It also relates to input buffers (and file reading) and io is somewhat messy in mp and on the agenda for cleaning up. (Luigi Scarso has done this with metafont, so that might be a starting point for experimenting.) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
Hi, On Aug 7, 2012, at 10:12 AM, Hans Hagen wrote:
On 7-8-2012 09:29, Keith J. Schultz wrote:
Hi Manuel, Everybody,
I am just getting into LuaLaTeX.
I needed to do some work with MetaPost.
While working I came across a kudo. That is once inside the mblibcode environment one can not call Lua. THIS I consider a missing feature and a VERY important one.
Some (simple) support for lua calls is on the (long term) agenda but not before the current mplib extensions project is done (i.e. the decimal calculation plugins).
Calling lua in itself is not so much an issue; after all one can just do a \directlua inside a blob of mp passed to mplib (I do that all the time).
I was under the impression that this was all that the proposed patch does. Luamplib did not allow any (tex nor lua) escapes within the block, if I understand correctly. Best wishes, Taco
On 7-8-2012 10:33, Taco Hoekwater wrote:
Hi,
On Aug 7, 2012, at 10:12 AM, Hans Hagen wrote:
On 7-8-2012 09:29, Keith J. Schultz wrote:
Hi Manuel, Everybody,
I am just getting into LuaLaTeX.
I needed to do some work with MetaPost.
While working I came across a kudo. That is once inside the mblibcode environment one can not call Lua. THIS I consider a missing feature and a VERY important one.
Some (simple) support for lua calls is on the (long term) agenda but not before the current mplib extensions project is done (i.e. the decimal calculation plugins).
Calling lua in itself is not so much an issue; after all one can just do a \directlua inside a blob of mp passed to mplib (I do that all the time).
I was under the impression that this was all that the proposed patch does. Luamplib did not allow any (tex nor lua) escapes within the block, if I understand correctly.
ok, so it's not a luatex/mplib issue but something for the maintainer of that package as deciding what characters need what catcode is a package issue (probably obeying \ { } is enough then) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com | www.pragma-pod.nl -----------------------------------------------------------------
participants (3)
-
Hans Hagen -
Keith J. Schultz -
Taco Hoekwater