Re: Filtering certain multi-line patterns from a file

It processes a 50,000 line file in about 70 milliseconds. ... I've heard Perl is a performant scripting language.

With those kinds of execution times, personally I wouldn't even worry about it to begin with. But just to demonstrate that Perl isn't going to be a lot slower, here's an example benchmark from my system (somewhat simple, just average execution time over a couple of runs). The first row is your code (unchanged), and the following three rows are the three pieces of code I posted:

	Input file size
Solution	12 lines	120_000 lines	1_200_000 lines
awk	26ms	66ms	417ms
awk to Perl	26ms	105ms	782ms
First example	27ms	75ms	520ms
Second example	27ms	72ms	450ms

This is Perl 5.24.1 on Linux. As you can see, although awk might have a minor advantage, I don't think you have anything to worry about in terms of speed when it comes to your use case. If it ever came to be an issue, there are lots of ways to optimize code in Perl (e.g. Benchmark and profilers like Devel::NYTProf).

Comment on Re: Filtering certain multi-line patterns from a file