Here docs

[Peter Stephenson <pws@ifh.de>]

I expect Zoltan's already fixed this, but anyway...

borsenkow.msk@sni.de wrote:
> On Thu, 1 Aug 1996, Peter Stephenson wrote:
> 
> > Anyone know the proper backslash rules for here documents?
> 
> Here is relevant part form XPG4 Shell:
> 
> 1. Section 2.7.4 (Here-document)
> 
> ...
> In this case, the backslash in the input will behave as the
> backslash inside double-quotes (see Section 2.2.3) However, the
> double-quote character (") will not be treated specially within a
> here-document, except when the double-quote appears within $(), ``, or
> ${}.

That's clear enough for here documents... the question is what should
happen at other times when zsh is parsing something in the same way.
This is usually when tokenising a string that hadn't already been
through the lexer, but is going to have some substitution arrangement
performed on it (this does not include many obvious cases like
$(...)).  If the answer is that \" should be left in this case too,
the fix is easy.

I believe this fix is right in all those cases for the following
reason: the code in dquote_parse() is specifically set up not to treat
unbackslashed " specially in these circumstances (test at line 1095 of
lex.c), so should not treat backslashed " specially either.

This should make Configure happier, any chance that it might work now?

There's a very minor difference left:
% cat <<EOS
> ${not_set:-\}}
> EOS

ksh gives \} and zsh gives } as output.  I like zsh's better.

*** Src/lex.c.bsqt	Wed Jul 24 16:34:31 1996
--- Src/lex.c	Thu Aug  1 15:29:18 1996
***************
*** 1001,1007 ****
  	    c = hgetc();
  	    if (c != '\n')
  		add(c == '$' || c == '\\' || (c == '}' && !intick && bct) ||
! 		    c == '\"' || c == '`' ? Bnull : '\\');
  	    else if (sub || unset(CSHJUNKIEQUOTES) || endchar != '"')
  		continue;
  	    break;
--- 1001,1007 ----
  	    c = hgetc();
  	    if (c != '\n')
  		add(c == '$' || c == '\\' || (c == '}' && !intick && bct) ||
! 		    (endchar && c == '\"') || c == '`' ? Bnull : '\\');
  	    else if (sub || unset(CSHJUNKIEQUOTES) || endchar != '"')
  		continue;
  	    break;


-- 
Peter Stephenson <pws@ifh.de>       Tel: +49 33762 77366
WWW:  http://www.ifh.de/~pws/       Fax: +49 33762 77330
Deutches Electronen-Synchrotron --- Institut fuer Hochenergiephysik Zeuthen
DESY-IfH, 15735 Zeuthen, Germany.