Hello Monks,

What am I doing wrong here? I read a line of text and do a simple match. Because I want to Do It Right, I use /x. And it Doesn't Work. The lines look like this: 

000.000.002.249-2-P  09-11-2007 15:27:30         102_Low_Alarm
000.000.002.249-2-P  09-11-2007 16:44:18         102_Low_Alarm
000.000.002.249-2-P  09-11-2007 16:44:18         202_Low_Repeat

[download]

and the code is below :

while (<>) {
  chomp;
   my ($meter,$dt,$type) =
     ($_ =~ (\S+)   #ser no
             \s+
            (\d\d-\d\d-\d\d\d\d \d\d:\d\d:\d\d)  # 12-11-2007 13:51:30
             \s+
            (\S+)  #102_Low_Alarm
             $/x);
  ....
}

[download]

Running under -d, I get this:

  DB<15> ($a,$b,$c)= ($line =~ m/(\S+)\s+(\d\d-\d\d-\d\d\d\d \d\d:\d\d
+:\d\d)\s+(\S+)$/x ) ;

  DB<16> x ($a,$b,$c)
0  undef
1  undef
2  undef

  DB<17> ($a,$b,$c)= ($line =~ m/(\S+)\s+(\d\d-\d\d-\d\d\d\d \d\d:\d\d
+:\d\d)\s+(\S+)$/ ) ;
  
  DB<18> x ($a,$b,$c)
0  '000.000.002.249-2-P'
1  '09-11-2007 15:27:30'
2  '102_Low_Alarm'

  DB<19> x $line
0  '000.000.002.249-2-P  09-11-2007 15:27:30  102_Low_Alarm'

[download]

I've just checked and it's not an artefact of running in the debugger; I made 2 versions with and without the /x, and they run differently. I'm obviously missing something very ... obvious.

This signature no verb

In reply to Unexpected behaviour of /x Regexp modifier? by jvector

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