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Names of variable, fields, or functions have a maximum of 64 characters, must begin with A-Z,a-z, or _, and can continue with those characters or 0-9. Definition of new types
Let's start with the bad news: it is impossible, in Quake-C, to define new types. That means for instance that you cannot create a type named ammo, derived from float, that will only be used to store ammo count. So much for the clean programming habits.