Hello,

First of all, sorry for providing insufficient information about my problem. I understand now, that I need to explain my problem clearly for me to get some help.

OK. Here goes..

I am trying to find a few strings (stored in array) from about 50,000 lines of code in a file. After finding, I'm doing some changes to the matched strings and writing it to another file. To accomplish this task, I'm assigning 5 regexes to five variables. 

foreach my $ur (@strings_to_be_matched)
{
     $reg1 = qr/\=/i;
     $reg2 = qr/\S+\=\S+/i;            
     $reg3 = qr/extern.+\b$ur\b\s*/i;
     $reg4 = qr/;$/i;                       
     $reg5 = qr/.+\b$ur\b\s*/i;

     foreach my $line (@contents_of_file)
{

     if(($ln =~ $reg3 and $ln =~ $reg4)){
     <some code>
     }

     if(($ln =~ $reg5 and $ln=~ $reg4 and ($ln !~ $reg1 or $ln =~ $reg
+2))
     {
     <some code>
     }
     

     if(($ln =~ $reg3 and $ln !~ $reg4)){
     <some code>
     }

     if(($ln =~ $reg5 and $ln !~ $reg4 and $ln !~ $reg1))
     {
     <some code>
     }

   }

}

[download]

I'm using "qr" to pre-compile my regexes, so that I can reduce the time taken. I feel $reg5 is causing the problem here. The if conditions which involve $reg5 take longer time to match. 

if (($ln =~ $reg5 and $ln=~ $reg4 and ($ln !~ $reg1 or $ln =~ $reg2)))
{
<some code here...>
}

if (($ln =~ $reg5 and $ln !~ $reg4 and $ln !~ $reg1)) 
{
<some code here...>
}

[download]

Another point to be noted is that, there are a few lines in the file which have a length of about ~12000. These lines take 4 seconds each to be processed.I want to reduce the time taken as few seconds taken to process each line are adding up to ~30 minutes. This is not acceptable at all in my case.

In reply to Re^6: Using regex with a variable by Praveen Dharmaraj
in thread Using regex with a variable by Praveen Dharmaraj

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