PATCH: 3.1.4: universal-argument upgrade

[Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>]

"Bart Schaefer" wrote:
> } I couldn't see a way of doing this without
> } adding a new flag, though that doesn't mean there isn't one.
> 
> Has the whole multiplier thing become more complicated than necessary in
> 3.1.4?  MOD_TMULT obviously does more than the `gotmult' global in 3.0.5
> did.

Looks like it, I have to admit I was confused to begin with.

> } Is there any enthusiasm for upgrading universal-argument to do what
> } emacs does, that is to take any following digits as part of the
> } argument?
> 
> YES!  That would be so much easier than having to clamp down Alt or hit
> ESC repeatedly to enter the digits.  Just remember that it also needs
> to take a following `-' as part of the argument.

OK, here it is.  This replaces the previous patch, since instead of
MOD_NEG I use MOD_REPL:  a 4 from universal-argument becomes
replaceable in the same way as a -1 from neg-argument.  It remains
unbound by default.  It's annoying that ^U for backward-kill-line is
so engrained in the shell-user psyche.

The only compatibility issue is that you can't repeat digits with
universal-argument, i.e (after rebinding universal-argument to ^U)
^U2 doesn't give you four twos any more, for obvious reasons.  I take
it this is entirely minor.

Is it OK to assume 0..9 and - are bound to self-insert?  It's a little
messier to test for them earlier: the problem is that you can't tell
after you've retrieved the binding whether it was a real `0' etc. or a
multi-key sequence ending in `0' such as `^X0', since that information
is buried inside getkeymapcmd() --- which I don't want to hack about
--- and on the latter occasion you certainly don't want digit-argument
behaviour.  It means it won't work in vi command mode, although the
digit handling is in any case different there.  (Actually, that's a
partial lie: unless you attempt to enter a -, it looks like it works
OK because the normal vi digit behaviour comes into play after you
enter universal-argument, i.e. the latter is then ignored.)

*** Doc/Zsh/zle.yo.mult	Sun May 11 13:24:01 1997
--- Doc/Zsh/zle.yo	Sat Oct 10 18:06:25 1998
***************
*** 779,785 ****
  )
  tindex(universal-argument)
  item(tt(universal-argument))(
! Multiply the argument of the next command by 4.
  )
  enditem()
  texinode(Completion)(Miscellaneous)(Arguments)(Zsh Line Editor)
--- 779,792 ----
  )
  tindex(universal-argument)
  item(tt(universal-argument))(
! Multiply the argument of the next command by 4.  Alternatively, if
! this command is followed by an integer (positive or negative), use
! that as the argument for the next command.  Thus digits cannot be
! repeated using this command.  For example, if this command occurs
! twice, followed immediately by tt(forward-char), move forward sixteen
! spaces; if instead it is followed by tt(-2), then tt(forward-char),
! move backward two spaces.  Note that this assumes the digits and dash
! are bound to tt(self-insert), as is usually the case.
  )
  enditem()
  texinode(Completion)(Miscellaneous)(Arguments)(Zsh Line Editor)
*** Src/Zle/zle.h.mult	Thu Jul  9 13:27:28 1998
--- Src/Zle/zle.h	Sat Oct 10 18:04:44 1998
***************
*** 90,95 ****
--- 90,97 ----
  #define MOD_TMULT (1<<1)   /* a repeat count is being entered */
  #define MOD_VIBUF (1<<2)   /* a vi cut buffer has been selected */
  #define MOD_VIAPP (1<<3)   /* appending to the vi cut buffer */
+ #define MOD_REPL  (1<<4)   /* current tmult is replaceable */
+ #define MOD_UNIV  (1<<5)   /* universal argument in progress */
  
  /* current modifier status */
  
*** Src/Zle/zle_misc.c.mult	Thu Jul  9 12:04:41 1998
--- Src/Zle/zle_misc.c	Sat Oct 10 17:48:56 1998
***************
*** 62,67 ****
--- 62,76 ----
  {
      char s[3], *p = s;
  
+     if (zmod.flags & MOD_UNIV) {
+ 	if (c >= '0' && c <= '9') {
+ 	    digitargument();
+ 	    return;
+ 	} else if (c == '-' && (zmod.flags & MOD_REPL)) {
+ 	    negargument();
+ 	    return;
+ 	}
+     }
      if(imeta(c)) {
  	*p++ = Meta;
  	c ^= 32;
***************
*** 442,448 ****
  
      if (!(zmod.flags & MOD_TMULT))
  	zmod.tmult = 0;
!     zmod.tmult = zmod.tmult * 10 + sign * (c & 0xf);
      zmod.flags |= MOD_TMULT;
      prefixflag = 1;
  }
--- 451,463 ----
  
      if (!(zmod.flags & MOD_TMULT))
  	zmod.tmult = 0;
!     if (zmod.flags & MOD_REPL) {
! 	/* If we just had a negative or universal argument, this is *
! 	 * the digit, rather than the -1 or 4 at first assumed.     */
! 	zmod.tmult = sign * (c & 0xf);
! 	zmod.flags &= ~MOD_REPL;
!     } else
! 	zmod.tmult = zmod.tmult * 10 + sign * (c & 0xf);
      zmod.flags |= MOD_TMULT;
      prefixflag = 1;
  }
***************
*** 451,462 ****
  void
  negargument(void)
  {
!     if(zmod.flags & MOD_TMULT) {
  	feep();
  	return;
      }
      zmod.tmult = -1;
!     zmod.flags |= MOD_TMULT;
      prefixflag = 1;
  }
  
--- 466,478 ----
  void
  negargument(void)
  {
!     if((zmod.flags & MOD_TMULT) && 
!        (zmod.flags & (MOD_REPL|MOD_UNIV)) != (MOD_REPL|MOD_UNIV)) {
  	feep();
  	return;
      }
      zmod.tmult = -1;
!     zmod.flags |= MOD_TMULT|MOD_REPL;
      prefixflag = 1;
  }
  
***************
*** 465,471 ****
  universalargument(void)
  {
      zmod.tmult *= 4;
!     zmod.flags |= MOD_TMULT;
      prefixflag = 1;
  }
  
--- 481,487 ----
  universalargument(void)
  {
      zmod.tmult *= 4;
!     zmod.flags |= MOD_TMULT|MOD_UNIV|MOD_REPL;
      prefixflag = 1;
  }
  
  
-- 
Peter Stephenson <pws@xxxxxxxxxxxxxxxxx>       Tel: +39 050 844536
WWW:  http://www.ifh.de/~pws/
Dipartimento di Fisica, Via Buonarotti 2, 56100 Pisa, Italy