Squid Reverse Proxy: exclude specific URI path?

[aeleus]

I'm using Squid Reverse proxy.

I created a Mapping where the URI is http://www.domain.com

That works fine with any URL that starts with http://www.domain.com and has any path after it such as http://www.domain.com/path.

I want to exclude specific paths while still allowing all other paths.

Exclude: http://www.domain.com/path-a

Allow: http://www.domain.com/any-other-path

How do I do this?

pfSense 2.3.3-RELEASE-p1
Squid package 0.4.36_2