Expressions aren't exposed to script
Construct's event sheets fundamentally work differently to code. Consequently object expressions that you may enter in to conditions and actions are not directly accessible from script. Refer to the scripting reference for the methods and properties that are directly accessible from scripts. You can also still indirectly access things that are not directly exposed to scripts by passing values between scripts and event sheets - for an example of that see integrating events with script.
export syntax. It also has a few differences to the legacy "classic" mode scripts, notably:
- Each module (script file) has its own top-level scope. This means top-level declarations are not globally accessible. Instead prefer to use imports and exports, or if you have to, explicitly use properties of
globalThis to make them global.
- Modules run code in strict mode. This eliminates common problems such as silent errors, typos accidentally creating variables, and fixes some aspects of the language considered mistakes. In particular it helps avoid confusing problems that beginners often run in to. Since all code is already run in strict mode, there is no need to add the
"use strict" directive to any of your code.
When the Use worker project property is Yes, the Construct runtime is hosted in a Web Worker instead of in the DOM, and renders using an OffscreenCanvas. This is generally good for performance since the runtime can run independently of the browser main thread, which can be blocked by browser tasks like layout. However Web Workers have a reduced set of APIs available. Notably there are no
document objects available, and so the DOM cannot be directly accessed. However there are many other APIs still available, such as fetch (and the older XMLHttpRequest), IndexedDB, WebSocket and others - see Functions and classes available to workers for more details.
Accessing global scope
window object is used to refer to global scope, such as with
window.myGlobal = 1;. Note however that the
window object is not available in worker mode, so this won't work there.
The standard way of accessing the global scope is with
globalThis, such as with
globalThis.myGlobal = 1;. Since this is available in both the DOM and Web Workers, this code will work everywhere. Construct also polyfills this if it is missing, so there is no need to worry about browser support.
In a browser context you can also use
Note many older code examples across the web use an older style designed to support defunct browsers. For example many old code examples use
const are preferred. Bear this in mind when looking at other code examples, and note there may be modern features that can considerably simplify the code. It can be a good idea to update any code snippets you use in your projects to a modern style.
Note this only applies to the Construct engine - all other browser APIs are of course available for use.