03-01-2018
This is my personal feeling: It is well known that any dedicated compiled program, be it C, C++, Pascal, or other, usually benefit from increased execution speed compared to e.g. scripts. But there is a tradeoff in terms of flexibility vs. e.g. awk, perl esp. when it comes to text analysis and processing, and adapting / modelling algorithms, for which those were specifically targeted / designed.
I'd be very interested in any results comparing execution times of your C++ with an equivalent awk script, as they both will use the same regex system calls.
Last edited by RudiC; 03-01-2018 at 04:57 AM..
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LEARN ABOUT MOJAVE
english5.18
English(3pm) Perl Programmers Reference Guide English(3pm)
NAME
English - use nice English (or awk) names for ugly punctuation variables
SYNOPSIS
use English;
use English qw( -no_match_vars ) ; # Avoids regex performance penalty
# in perl 5.16 and earlier
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if ($ERRNO =~ /denied/) { ... }
DESCRIPTION
This module provides aliases for the built-in variables whose names no one seems to like to read. Variables with side-effects which get
triggered just by accessing them (like $0) will still be affected.
For those variables that have an awk version, both long and short English alternatives are provided. For example, the $/ variable can be
referred to either $RS or $INPUT_RECORD_SEPARATOR if you are using the English module.
See perlvar for a complete list of these.
PERFORMANCE
NOTE: This was fixed in perl 5.20. Mentioning these three variables no longer makes a speed difference. This section still applies if
your code is to run on perl 5.18 or earlier.
This module can provoke sizeable inefficiencies for regular expressions, due to unfortunate implementation details. If performance matters
in your application and you don't need $PREMATCH, $MATCH, or $POSTMATCH, try doing
use English qw( -no_match_vars ) ;
. It is especially important to do this in modules to avoid penalizing all applications which use them.
perl v5.18.2 2014-01-06 English(3pm)