From: Hans Hagen <pragma@wxs.nl>
To: ntg-context@ntg.nl
Subject: Re: MetaPost label direction prefix
Date: Sat, 24 Aug 2013 02:28:34 +0200 [thread overview]
Message-ID: <5217FE32.7070909@wxs.nl> (raw)
In-Reply-To: <20130823131450.GI18239@homerow>
On 8/23/2013 3:14 PM, Marco Patzer wrote:
> On 2013–08–23 Hans Hagen wrote:
>
>>> Is this prefix required? It breaks old code and required a branch in
>>> every new project. And I don't really see a reason for this
>>> incompatibility. Here is an example defining a new direction “foo”:
>>
>> The MpIV code has namespace protection. Why run traditional in MkIV?
>>
>>
>>> \starttext
>>> \startMPcode
>>> label("first", origin);
>>>
>>> %% MkIV
>>> %% pair mfun_laboff.foo ; mfun_laboff.foo := (.5,-1) ;
>>> %% mfun_labxf.foo := mfun_labyf.foo := 1 ;
>>>
>>> %% MkII
>>> pair laboff.foo ; laboff.foo := (.5,-1) ;
>>> labxf.foo := labyf.foo := 1 ;
>>>
>>> label.foo("second", origin);
>>> \stopMPcode
>>> \stoptext
>>
>> I wasn't aware of users defining extra ones. I'll add this:
>
> Probably not many users will tinker with custom label directions,
> but MetaPost package authors do. Some packages like piechartmp¹
> internally use laboff.foo and the mpfun_ prefix breaks those
> packages. They work in traditional MetaPost, plain TeX, LaTeX and
> ConTeXt MkII, but since mplib uses the mpfun_ prefix, those packages
> are broken in MkIV.
that kind of tinkering can also result in overloading context 'extensions'
>> […]
>> installlabel.foo ( 0, 1, 1, (.5,-1) ) ;
>
> This does not fix the problem since it only *defines* the correct
> variant, it doesn't help *using* those values. If the label values
> are being changed in the package one still has to branch out to
> support both variants. And even if there was an abstraction
> assisting to *use* the laboff values, all MetaPost packages
> tinkering with laboff would need to be adjusted. I can't imagine
> that to happen. Here's what the piechartmp package is doing, for
> instance:
I'll provide:
\starttext
\startMPcode
startplaincompatibity ;
label("first", origin);
pair laboff.foo ; laboff.foo := (.5,-1) ;
labxf.foo := labyf.foo := 1 ;
label.foo("second", origin);
stopplaincompatibity ;
\stopMPcode
\stoptext
As I wouldn't be surprised if there were more differences we need to
handle.
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
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://tex.aanhet.net
archive : http://foundry.supelec.fr/projects/contextrev/
wiki : http://contextgarden.net
___________________________________________________________________________________
next prev parent reply other threads:[~2013-08-24 0:28 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-23 9:42 Marco Patzer
2013-08-23 12:48 ` Hans Hagen
2013-08-23 13:14 ` Marco Patzer
2013-08-24 0:28 ` Hans Hagen [this message]
2013-08-24 12:31 ` Marco Patzer
2013-08-25 11:49 ` Hans Hagen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=5217FE32.7070909@wxs.nl \
--to=pragma@wxs.nl \
--cc=ntg-context@ntg.nl \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).