how do I set up so I don't have to state \Other\ when using a class?
Don't strive for not using namespaces.
Not using namespaces makes only sense for really small scripts, which run standalone and don't reuse pieces of code from other vendors (components/libraries).
I still don't understand why $mustache = new Mustache_Engine(); doesn't have to be $mustache = new \Mustache\Mustache_Engine();
Mustache_Engine is not namespaced (yet).
They use a string-prefix-namespace: they simply add Mustache_ to the classname Engine to avoid class name collision with other classes called Engine. This code will run on old and newer PHP versions.
Eventually, it will be come \Mustache\Engine, when the Mustache developers update the code to make use of namespaces. This code will only run on PHP versions, which support namespaces as a language feature.
Autoloading of Mustache
If you installed Mustache using Composer
{
"require": {
"mustache/mustache": "^2.9"
}
}
then Composer will generate the autoloading for Mustache automatically.
You don't have to add a PSR-0 directive to composer.json to get it working.
You only need to set PSR-0, if you downloaded and extracted Mustache manually into the /lib folder. This is the old way of working with dependencies - leverage Composer instead.