Hacker News Reader

Comment by gpvos | Hacker News Reader

I find it weird to have the Perl innovation (?:...) be called "traditional regex". Perl was rather innovative back then, even if it's more than 30 years ago now. Traditional regex is what came before it (grep -E being the most advanced form). I wonder what counts as nontraditional in the author's eyes.

View on HN

>even if it's more than 30 years ago now.

Here's your answer.

>Traditional regex is what came before it

No, that's "ancient regex".

> No, that's "ancient regex".

wouldn't the "ancient regex" be the ed "g/re/p" version?

  -E, --extended-regexp
    Interpret PATTERNS as extended regular expressions (EREs, see below).
  -G, --basic-regexp
    Interpret PATTERNS as basic regular expressions (BREs, see below).  This is the default.
  -P, --perl-regexp
    Interpret I<PATTERNS> as Perl-compatible regular expressions (PCREs).  This option is experimental when combined with the -z (--null-data) option, and grep  -P  may  warn of unimplemented features.

From the manpage it seems my grep make distinction between "Extended" "Basic" and "Perl" regexes.

>wouldn't the "ancient regex" be the ed "g/re/p" version?

That's "prehistoric regex"

In my head a regex-like thing of Perl origin is known as a 'perlex'.

can call it PCRE now

'PCRE' never really caught on broadly, unfortunately.

It seems that Boost actually uses 'perlex' https://www.boost.org/doc/libs/1_31_0/libs/regex/doc/syntax_... .

Haha, you're right about that. I was looking for another word for "default"

Reply on news.ycombinator.com