Global keyword

The global keyword is used to define global variables. Global variables are the only way to define a mutable variable outside of the scope of a function. Global variables are also used for importing external data which can be provided while the Wasm module is being instantiated.

Example

This example imports the `window.setInterval` function from Javascript to run a function every second which repeatedly increments the global variable.

Global variables can also be more complicated types like being multivalued, GC heap types, arrays, etc.