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From: allbery@NCoast.ORG (Brandon S. Allbery KB8JRR)
Newsgroups: comp.lang.perl
Subject: Re: s///e bizarreness
Message-ID: <1991Jan3.232855.7457@NCoast.ORG>
Date: 3 Jan 91 23:28:55 GMT
References: <1991Jan3.043016.27394@uvaarpa.Virginia.EDU> <1991Jan03.123139.13432@convex.com>
Reply-To: allbery@ncoast.ORG (Brandon S. Allbery KB8JRR)
Followup-To: comp.lang.perl
Organization: North Coast Computer Resources (ncoast)
Lines: 29

As quoted from <1991Jan03.123139.13432@convex.com> by tchrist@convex.COM (Tom Christiansen):
+---------------
| From the keyboard of marc@mit.edu:
| :% perl -e '$_="|2+2|";s/\|([^\|]*)\|/$1/e;print "$_\n";'
| :2+2
| :% perl -e '$_="|2+2|";s/\|([^\|]*)\|/$1/ee;print "$_\n";'
| :4
| 
| The reason case 2 says what it does is that $1 as an expression is just
| "2+2".   On the other hand , "3+$1" does yield 7, not 3+2+2, so maybe just
| maybe it really is a buglet, as I don't quite see why $1 shouldn't be 4
+---------------

It must be a bug --- otherwise, you would *need* to use /e to get $1, ... to
expand on the RHS.  Which is not and has never been the case.

+---------------
| The really unexpected thing here is that /ee yields a double eval.  
+---------------

You can say *that* again!  I just about fell out of my chair when I saw the
"/ee" and its result.

++Brandon
-- 
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