So I wrote a Perl script about 5 months ago to parse a rather strange text file. Here's a sample of the source file: 
AACE_1:
{
 class: mic_if_win,
 label: "!AACE.*",
 mic_if_handles_windows: 1
}
{
 rtree_state: close,
 ltree_state: close
}
AACE_1."ADDR LINE1":
{
 class: field,
 id: 734
}

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etc. (For those who may recognize it, it's a GUI Map file used by WinRunner, an automated testing suite.) Each header of a braced chunk is either a screen (green-scren) name or field name - the field names have the screen name they're on, followed by ".", followed by the field name. To determine whether I'm on a line that contains a screen name, I use this line: 
if ($desc != 0 and /^([^.]+):$/) {
    # do stuff
}

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Looking at that regex now, I think, it'd be smarter to use 
/^(\w+):$/

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but that's not the issue. Both the original regex and the one I have above produce this warning for each and every line of input: 
Use of uninitialized value in concatenation (.) or string at ./genguim
+apdoc.pl line 52, <GUIFILE> line n.

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WTF? This script worked perfectly 5 months ago. The input file has not changed, nor has the script. Is there something fundamentally wrong with the regex?

In reply to Code rot? by aarestad

Title:
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