Hi I have tried the following code to conditionally substitute a variable string with another variable string, but its not working. Can anyone please let me know why or point me to another similar solution already discussed before? Thanks 

my $cell_name ="xyz";
while (<FILE>){
        if($_ =~ /STARTING_PATTERN\s+(.*)/){
            $string=$_;
            $sub=$1;
            
            $string =~ s/$sub/$cell_name/ ;
            
            }                                
    }                                        
    close FILE;

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If my <FILE> contains the line with the string "STARTING_PATTERN RRR" it should be replaced by "STARTING_PATTERN xyz". Please remember $cell_name is not always "xyz" - its a variable, I have just used "xyz" for illustration purpose here.

In reply to Trying to substitute a variable with another variable in a string but not working by kaushik9918

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