Hi, I have a file. I want that lines which match certain patterns remain rest dont. So I have an array which I will call grep_array. Each element of that array is a regexp So I can do 
open file
@some_array = <file>
foreach $pattern (@matcharray) {
  grep {/$pattern/}@some_array
}

[download]
Is there a more efficient way? @some_array can be very very large file. So first creating such a big array and then parsing it so many times looks inefficient. Moreover this will spoil the order. I want to find all lines which match the list of regexps.

In reply to Usage of grep on a file by tsk1979

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