On 2020-07-18 02:59, davidson wrote:
On Thu, 16 Jul 2020 Ajith R wrote:
On Thursday 16 July 2020 4:54:09 AM IST davidson wrote:
[snip]
$ sed 'y/\xc2\xa0/%/' somefile
An off topic question: of sed, awk and perl, if I am to chose one to
learn, which would you suggest. I wanted to do some substitutions. I
read about them and decided on PERL because from what I understood,
it has better support for regular expressions and do almost
everything that sed and awk could do. Have I made the right
decision?
If your focus is regular expressions, then you should read "Mastering
Regular Expressions", 3rd Edition:
https://www.oreilly.com/library/view/mastering-regular-expressions/0596528124/
The author compares and contrasts regular expression capabilities in
various tools. I seem to recall that he puts Perl at the top of the
heap, and notes that Perl compatible regular expressions (PCRE) are
available via libraries in other programming languages.
I will also say that I have used Perl for 20+ years, and Perl has
allowed me to expand my knowledge and skills tremendously. I have
accomplished a lot of useful work with Perl.
As the Perl slogan goes, "There is more than one way to do it". Perl
delivers.
Another slogan starts with "Perl makes easy things easy", but I have my
doubts about the second half "makes hard things possible".
20 years ago, Moore's Law ruled. You bought a new Pentium computer
every year and a half, and your Perl script ran faster.
Today, Amdahl's Law rules. You buy a new Core or Ryzen chip every year
and a half and your Perl script runs at the same speed.
Perl is fundamentally a sequential programming language. Concurrent
programming was bolted on with a library, and that library has a huge
disclaimer:
https://metacpan.org/pod/threads
"WARNING
The "interpreter-based threads" provided by Perl are not the fast,
lightweight system for multitasking that one might expect or hope
for. Threads are implemented in a way that make them easy to misuse.
Few people know how to use them correctly or will be able to provide
help.
The use of interpreter-based threads in perl is officially
discouraged."
Being the lazy, impatient, and over-proud Perl programmer that I am, I
disregarded the above and have been working on a Perl library for
multi-threaded flow-based programming. OMG. I don't know if I can or
will succeed. It is the most difficult Perl code I have ever worked on.
I have experimented with Go in the past. I plan to start learning
Erlang shortly.
David
