zsh propmts

[Robert Stone <rstone@xxxxxxxxxxxxx>]

	I'd like to thank everyone who had anything to do with the "%_" 
value for PS2 in zsh-3.0.0, I'm in love with it.

	I've been attempting to set up a prompt that will show me any 
non-zero return values, and print the names of any signal the last job 
recieved.  Right now I'm using two features of the shell to accomplish this:

function precmd { PSVAR=$signals[$?^128+1] }
PROMPT='%(?..%1(?.{%?}.%B{%?%2(v.. %v)}%b) )%m:%~%# '

	Unfortunately I end up with $PSVAR = '.' if no signal has occured 
because an invalid array subscription produces '.', such that my prompt 
looks like:

aic1:~% return 15
{15 .} aic1:~% ls -l            # I hit ^C here
{130 INT} darkstar:~%

	The trick here is that I can't execute anything in precmd that would 
effect $? or the "%?" value in the prompt is inaccurate.  How could I clean 
this so that PSVAR is set to a null string when $signals is given an invalid 
subscript?
							thanks,
							Robert Stone

------------------rstone@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
#!/bin/perl -sp0777i<X+d*lMLa^*lN%0]dsXx++lMlN/dsM0<j]dsj
$/=unpack('H*',$_);$_=`echo 16dio\U$k"SK$/SM$n\EsN0p[lN*1
lK[d2%Sa2/d0$^Ixp"|dc`;s/\W//g;$_=pack('H*',/((..)*)$/)