If you have ever been using Java, you may already be familiar with .properties file format. This is a simplistic configuration file format, somewhat similar to INI:

# Comment
key = Value

For ones not liking that, there's also alternative syntax:

! Comment
key: Value

Where leading/trailing spaces are optional and are trimmed in parsing process.

Since I've seen people ask about this kind of thing, and also have seen people invent ridiculous (and non-functional) regular expressions to parse this file format, I thought that I may as well make an implementation that works "just right".