Question

I am using the following code:

preg_match('%^(\w+)(/(\w+))?$%', $pathInfo, $matches);

to parse a url string.
Can somebody can explain me what this expression parse?
Because it works great with /example, but with /example one, or /example-one doens’t work anymore for $matches[1]. Thanks!

Answer 1

It doesn’t work because \w matches alphanumeric characters plus an underscore. It will not match a hyphen and a space.

Short solution: add them to a character class, turn \w into [\w -].

Long solution: use normal* (special normal*)* to minimize the amount of backtracking, with normal being \w and special being [- ]:

%^(\w+(?:[- ]\w+)*)(/(?:\w+(?:[- ]\w+)*))?$%