Re: Patterns: Why are anchors not character classes?

[Dirk Laurie <dirk.laurie@...>]

2015-07-14 18:21 GMT+02:00 John Hind <john.hind@zen.co.uk>:
> I've just had another bout of wrestling with patterns, probably the most
> obscurantist part of Lua and the only bit I've never been able to learn and
> always have to get "Programming in Lua" off the shelf.

Oh, I just use the online manual and pick the last string function in
the index. The patterns come immediately after. I can't remember
all of them either. :-)

> Take the simple case of parsing a comma-separated list

That's [^,]+ or [^,]* depending on whether empties are allowed.

> If the start and end anchors behaved like character classes we could do
> better. For regularity they probably should be %^ and %$

An interesting notion. I'll probably use it.

> The other thing I'd like to see is some "standard" patterns as constants in
> the string library for the common functions that a C programmer for example
> will miss ("trimright", "trimleft" and "trim", for example).

Well, now. A little module that monkeypatches those into the string library
is surely not too hard?