On 2021-Feb-23, Tom Lane wrote: > * Create infrastructure to allow treating \w as a character class > in its own right. (I did not expose [[:word:]] as a class name, > though it would be a little more symmetric to do so; should we?)
Apparently [:word:] is a GNU extension (or at least a "bash-specific character class"[1] but apparently Emacs also supports it?); all the others are mandated by POSIX[2]. [1] https://en.wikibooks.org/wiki/Regular_Expressions/POSIX_Basic_Regular_Expressions [2] https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03_05 I think it'd be fine to expose [:word:] ... > [1] https://www.regular-expressions.info/charclasssubtract.html I had never heard of this subtraction thing. Nightmarish and confusing syntax, but useful. > + Also, the character class shorthands <literal>\D</literal> > + and <literal>\W</literal> will match a newline regardless of this mode. > + (Before <productname>PostgreSQL</productname> 14, they did not match > + newlines in newline-sensitive mode.) This seems an acceptable change to me, but then I only work here. -- Álvaro Herrera 39°49'30"S 73°17'W
