Re: OR, quantifier support in Lua patterns

[Jay Carlson <nop@...>]

I take no position on the suitability of this implementation.

On 2018-10-09, at 5:47 PM, Victor Krapivensky <krapivenskiy.va@phystech.edu> wrote:

> I am not sure why everybody seems to believe that (non-PCRE) regular
> expression engine has to be complex. See
> https://swtch.com/~rsc/regexp/regexp1.html for implementation in less than
> 400 lines of C (probably less rewritten in a "modern" style).

Counting semicolons:

$ cat *.c *.h | tr -c -d ';' | wc
      0       1     656

Using https://dwheeler.com/sloccount/

$ sloccount regcomp.c regcomp.h regerror.c regerror.h regexec.c regsub.c regaux.c rregexec.c rregsub.c
[...]
Totals grouped by language (dominant language first):
ansic:         1139 (100.00%)
[...]

But with clang -O2 on Darwin-x86_64:

$ gsize --total -d libregexp9.a  | tail -1
  10500	      0	    752	  11252	   2bf4	(TOTALS)

And with clang -Os, it's 8293 bytes. gcc -Os on Linux is 7503 bytes.

-- 
Jay