code that used to work that doesn't anymore

code that used to work that doesn't anymore

[Mikael Magnusson]

No idea if this was meant to be valid syntax, but used to run:
% zselect -t ${$(( $1 * 100 ))%.[0-9]#}
zsh: bad substitution

This works both now and before:
% zselect -t ${${:-$(( $1 * 100 ))}%.[0-9]#}

NB: this is perhaps the most unexpected result of my life
% echo ${:-$[5]}
5
% echo ${$[5]}
7
But it's simply element five of $$ (pid of zsh).

I guess the ${$ in my first command is now interpreted as a $$ and
then the (( is nonsense?

-- 
Mikael Magnusson

Re: code that used to work that doesn't anymore

[Peter Stephenson]

On Sun, 22 Feb 2015 22:07:24 +0100
Mikael Magnusson <mikachu@gmail.com> wrote:
> No idea if this was meant to be valid syntax, but used to run:
> % zselect -t ${$(( $1 * 100 ))%.[0-9]#}
> zsh: bad substitution

It appears that's supported, but there was no test for it so it didn't
get picked up as a change.

diff --git a/Src/subst.c b/Src/subst.c
index 176a004..f52bcdf 100644
--- a/Src/subst.c
+++ b/Src/subst.c
@@ -2217,12 +2217,28 @@ paramsubst(LinkList l, LinkNode n, char **str, int qt, int pf_flags)
      */
     idbeg = s;
     if ((subexp = (inbrace && s[-1] && isstring(*s) &&
-		   (s[1] == Inbrace || s[1] == Inpar)))) {
+		   (s[1] == Inbrace || s[1] == Inpar || s[1] == Inparmath)))) {
 	int sav;
 	int quoted = *s == Qstring;
+	int outtok;
 
 	val = s++;
-	skipparens(*s, *s == Inpar ? Outpar : Outbrace, &s);
+	switch (*s) {
+	case Inbrace:
+	    outtok = Outbrace;
+	    break;
+	case Inpar:
+	    outtok = Outpar;
+	    break;
+	case Inparmath:
+	    outtok = Outparmath;
+	    break;
+	default:
+	    /* "Can't Happen" (TM) */
+	    DPUTS(1, "Nested substitution: This Can't Happen (TM)");
+	    return NULL;
+	}
+	skipparens(*s, outtok, &s);
 	sav = *s;
 	*s = 0;
 	/*
diff --git a/Test/C01arith.ztst b/Test/C01arith.ztst
index 67d78ee..d3176dd 100644
--- a/Test/C01arith.ztst
+++ b/Test/C01arith.ztst
@@ -300,6 +300,7 @@
   print $(( 0b2 ))
 1:Binary numbers don't tend to have 2's in
 ?(eval):1: bad math expression: operator expected at `2 '
+# ` for emacs shell mode
 
   integer varassi
   print $(( varassi = 5.5 / 2.0 ))
@@ -376,3 +377,10 @@
   esac))
 0:Would-be math expansion with extra parenthesis making it a cmd subst
 >Worked OK
+
+  (setopt extendedglob
+  set -- 32.463
+  print ${$(( $1 * 100 ))%%.[0-9]#})
+0:Arithmetic substitution nested in parameter substitution
+>3246
+ 

-- 
Peter Stephenson <p.w.stephenson@ntlworld.com>
Web page now at http://homepage.ntlworld.com/p.w.stephenson/