[tex-live] [dgc@ccrwest.org: [texhax] inconsistency between pdftex and tex]

[Karl Berry]

    Prepending pdf might be the right thing
    for pdftex, be we rely on some convention here and such things can
    easily fail.

Agreed.

    > Maybe we should just forget about %& altogether?

    I am unsure if there is some real use for this feature. 

I'll append the most relevant message I found in my archives from 1995,
when the feature got added.  In today's environment, I am not convinced.

    I know that it is used for the metapost -> tex (resp. latex)
    communication. But, is it useful for anything else in real life?

Why would it be needed for metapost->tex/latex?  If there is *any* real
life application, then it's probably worth keeping.

Thanks,
karl


Date: Wed, 15 Mar 1995 01:09:46 +0000 (GMT)
From: Laurence Yaffe <lgy at newton.phys.washington.edu>
To: kb at cs.umb.edu (K. Berry)
Cc: web2c-wizards at cs.umb.edu
Subject: Re: [rokicki at cs.stanford.edu: %& tricks?]

> Can anyone see any significant downside to this idea of Tom's?
> 
> From: Tomas G. Rokicki <rokicki at CS.Stanford.EDU>
> To: kb at cs.umb.edu
> Subject: %& tricks?
> Date: Tue, 14 Mar 95 13:07:03 -0800
> 
> On the NeXT I've found it useful to modify TeX so that, if no format is
> specified on the command line but a file name is specified on the command
> line, to open that file and take a sneak peak at the first line.  If the
> first line is
> 
> %&
> 
> followed by a `word', then that `word' is taken to be the format to open.
> Thus, for instance, one can have files like
> 
> %&latex
> 
> or  [...]
>
> and then these files become somewhat self-identifying.  The reason this
> was useful was because all of these files have icons that point at the
> TeXview program, yet TeXview handles many different formats.  I can also
> consider this useful in general on command-line systems and windowing
> systems.
> 
> The patch is, of course, totally trivial.

For years, I've used a similar scheme.  The only differences are that:

    a) I use a separate 'wrapper' program instead of modifying virtex itself,
    b) My wrapper looks for lines like: %format=latex

I have found that making all TeX files (regardless of what format they use)
self-identifying (so that 'tex some-file' is always sufficient to run them)
is very convenient.  I strongly support getting functionality of this sort into
the standard distribution.  Exactly what syntax to use is a minor detail --
I don't have any problem with Tom's choice.  Whether to use a separate
wrapper program, or modify virtex itself, is an implementation detail.
I'd be happy to see the functionality in virtex itself.

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