Re: alias vl="vi !$"

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

[Redirected to -workers]

On Mar 14,  4:27pm, Peter Stephenson wrote:
}
} Bart Schaefer wrote:
} > Inside a function, however, $_ has already been changed to be the last
} > word of the _currently executing_ command, the same as as $argv[-1].
} 
} It's not likely anyone's using the present form in a function; [...]

Unfortunately this is not as easily/cleanly changed as I'd hoped.

setunderscore() is called fairly early in execcmd() and uses the value
from getdata(lastnode(args)) before the "args" list is manipulated by,
e.g., the RM_STAR_SILENT and AUTO_CD code, and globlist().

Thereafter, execcmd() does a number of early "return"s, mostly in error
states.  Those can be changed to "goto"s down to the end of the function
(like "goto done" used in at least one spot) but I'm not sure if it's
safe to simply save a pointer to getdata(lastnode(args)) or if it'd have
to be dupstring()'d.

So it comes out something like this:

Index: Src/exec.c
===================================================================
RCS file: /extra/cvsroot/zsh/zsh-4.0/Src/exec.c,v
retrieving revision 1.16
diff -c -r1.16 exec.c
--- exec.c	14 Feb 2004 19:39:27 -0000	1.16
+++ exec.c	14 Mar 2004 17:53:44 -0000
@@ -1747,6 +1747,7 @@
     wordcode code;
     Wordcode beg = state->pc, varspc;
     FILE *oxtrerr = xtrerr;
+    char *underscore = "";
 
     doneps4 = 0;
     redir = (wc_code(*state->pc) == WC_REDIR ? ecgetredirs(state) : NULL);
@@ -1989,8 +1990,8 @@
 	text = NULL;
 
     /* Set up special parameter $_ */
-
-    setunderscore((args && nonempty(args)) ? ((char *) getdata(lastnode(args))) : "");
+    if (args && nonempty(args))
+	underscore = dupstring((char *) getdata(lastnode(args)));
 
     /* Warn about "rm *" */
     if (type == WC_SIMPLE && interact && unset(RMSTARSILENT) &&
@@ -2021,8 +2022,7 @@
 
     if (errflag) {
 	lastval = 1;
-        opts[AUTOCONTINUE] = oautocont;
-	return;
+	goto _return;
     }
 
     if (type == WC_SIMPLE && !nullexec) {
@@ -2104,8 +2104,7 @@
 	if ((pid = zfork()) == -1) {
 	    close(synch[0]);
 	    close(synch[1]);
-            opts[AUTOCONTINUE] = oautocont;
-	    return;
+	    goto _return;
 	} if (pid) {
 	    close(synch[1]);
 	    read(synch[0], &dummy, 1);
@@ -2130,8 +2129,7 @@
 		}
 	    }
 	    addproc(pid, text, 0);
-            opts[AUTOCONTINUE] = oautocont;
-	    return;
+	    goto _return;
 	}
 	/* pid == 0 */
 	close(synch[0]);
@@ -2500,6 +2498,8 @@
 
     zsfree(STTYval);
     STTYval = 0;
+ _return:
+    setunderscore(underscore);
     opts[AUTOCONTINUE] = oautocont;
 }
 

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

Zsh: http://www.zsh.org | PHPerl Project: http://phperl.sourceforge.net