Screeps modules code#

Screeps modules code#

And at this point in the processing, beta is undefined, and hence the execution of the function crashes you'll get a ReferenceError, module loading stops, and none of your code will run. In order to initialize charlie.foo, the JS module loader needs to execute pute(). The problem comes in the third statement. At this point, JS doesn't know what 'beta' is and it doesn't care it just processes it and stores the function. The second statement creates a property on that object, and assigns a function to it. The first statement in C.js creates a global variable, which is an empty Object. Screeps starts processing your main.js and sees the require it then creates a new module (internally), loads the file C.js, and starts processing. If you try to initialize a variable or property at the root level in a file with the result from a function, then that function is called immediately - in the middle of the loading process - and evaluated before the rest of your code has been seen. Code within a function isn't evaluated until it's executed, and functions only get executed when called - which is (generally) after all your code has been parsed. If you declare a function in C.js, any code within that function can access anything declared or created anywhere and everywhere - even globals not yet declared. You could instead declare a global variable inside a file (eg global.utils = // its value gets exportedДЄnd I'm only talking about the top level. Yet you don't have to call all of your code using required objects. If the same module is then required by another piece of code, then the loader just re-uses the results of its previous parse it doesn't re-load and re-parse the file. Every time you require a new module, it loads the code, parses it, and returns the module's exports to you wherein one normally puts the exports into a local variable that you then access throughout the new module. Yet what the runtime actually does is it just compiles your main.js file and ignores the rest they just happen to get included because they're mentioned by a require. In my day job, we use TypeScript rather than JS, and a lot of that is because we don't want to run into runtime errors, and that's hard to do without a lot of defensive coding - ie, asking if a property is present and non-null before accessing it.ДЄs part of the Screeps runtime, you generally write code in different modules and import them. Generally I'm not a fan of dynamic languages. If Screeps was written in a different language - or if you're using one of the other languages that Screeps supports, and if so then just ignore this whole post - the presence or absence of that property could be dictated by its type. As an interpreted language, you can call a function or access a property on an object with absolutely no idea if it's there or not.ДЄ lot of the Screeps objects have a pos property, but they don't have it because of inheritance, or because they conform to an interface they just have it. The same call can go not only to multiple places, but you don't even have to define the set of possible destinations. JS don't care! It only has to exist when the code is executed. Note that this works even though bar hasn't been defined at the point at which a call to it was written. For example, the following: // MyModule.js I got into this mess because I wanted a way to define several functions in a file, and have them call each other.