How can I brew link a specific version?

Question

I have a few kegs of the same package in /usr/local/Cellar/libfoo like /usr/local/Cellar/libfoo/1.0.1, /usr/local/Cellar/libfoo/HEAD a

Answer 1

If you have installed, for example, php 5.4 it could be switched in the following way to php 5.5:

$ php --version
PHP 5.4.32 (cli) (built: Aug 26 2014 15:14:01) 
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.4.0, Copyright (c) 1998-2014 Zend Technologies

$ brew unlink php54

$ brew switch php55 5.5.16

$ php --version
PHP 5.5.16 (cli) (built: Sep  9 2014 14:27:18) 
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2014 Zend Technologies