I finally had my first Perl class (three days of wonderful bliss. Yay!). Anyways, we were working on creating regexes to find different things, and the last regex block in my code (finding a negative number with a decimal) stumped everyone (even the teacher at the time). We wanted the regex to find all but the last line in my text file. My last regex finds the last six lines of my text file, but I don't want it to find the last line. Assuming that the "abc" in that last line could be anything, how do I exclude it if it doesn't follow the same pattern as the examples above it and not eliminate stuff I do want?

#!  c:\Perl\bin\perl5_8
#Read lines from a text file; create RE's that will find certain stuff
#use strict;   take this out for now

open (MYFILE, "< Lori.txt") || die("Can't open Lori.txt");

#find lines starting with a c and end with a d
print "lines starting with a c and end with a d:\n";

while (chomp($line =<MYFILE>))
    { 
      if ($line =~ /^[cC].*d$/o)
        { print "$line\n";
        }
    }

#find blank lines
seek MYFILE, 0,0;
print "\nblank lines:\n";

while (chomp($line =<MYFILE>))
    { 
      if ($line =~ /^$/o)
        { print "$line\n";
          print "blank line above\n";
        }
    }

#find lines with only spaces
seek MYFILE, 0,0;
print "\nlines with only spaces:\n";

while (chomp($line =<MYFILE>))
    { 
      if ($line =~ /^ *$/o)
        { print "$line\n";
          print "spaced out line above\n";
        }
    }

#find lines that contain the same number twice
seek MYFILE, 0,0;
print "\nlines that contain the same number twice:\n";

while (chomp($line =<MYFILE>))
    { 
      if ($line =~ /(\d+)[^\d]*\1[^\d]/o)
        { print "$line\n";
        }
    }

#find lines that contain a negative number with a decimal point
seek MYFILE, 0,0;
print "\nlines that contain a - number with a decimal point:\n";

while (chomp($line =<MYFILE>))
    { 
      if ($line =~ /-\d*\.\d*/o)
        { print "$line\n";
        }
    }

close MYFILE;
[download]

And my test text file Lori.txt:

Catdog isn't a horsebird
The next line is a blank line.

The next line is a line full of spaces.

fred1 fred2 fred3 fred3 fred2
lucy1 lucy2 lucy3 lucy4 lucy5
negative number with a decimal: -15.00
negative number with a decimal: -.15
positive number with a decimal: .15
negative number with a decimal: -7.
negative sign with a decimal: -.

Thanks for any insights you can provide. Please feel free to suggest ways of improving my code.    :-)

Lori

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