[htmltmpl] Parsing bug under Perl 5.6.1, and a fix

[Josh C. <jos...@mi...>]

Here's a strange bug that I encountered while running HTML::Template  
2.8 under Perl 5.006001 (doesn't happen in the various flavors of 5.8  
that I've tried).

When using a scalar reference template, HTML::Template dies on the  
first TMPL_XXX tag that it encounters: "Unknown or unmatched TMPL  
construct at /fake/path/for/non/file/template"

I tweaked the error string to include the value of $which when it  
dies, and I discovered that the TMPL_ portion of the first tag was  
always replaced by F0B5, no matter what the original tag. For example:

TMPL_VAR     -->  F0B5VAR
TMPL_INCLUDE -->  F0B5INCLUDE
TMPL_IF      -->  F0B5IF
etc.

The problem appears to be related to the uc function in line 1969:

     $which = uc($1); # which tag is it

Doing something with $1 (e.g. printing it or assigning it to a  
variable) before calling the uc function fixes the problem.

     $which = $1;
     $which = uc($1); # which tag is it

After making that change, the problem goes away and the template  
string is parsed as usual.

All best,
Josh