Baffling behaviour of string.match

[Dirk Laurie <dpl@...>]

I don't understand this.

--[[
> s='abbcd'; return a:match('b')
b
> s='abbcd'; return a:match('bb')
bb
> s='abbcd'; return a:match('b*')

>
--]]

I expected the last match to be also "bb".

Dirk