Array Types

Arrays are ordered immutable collections.

Example

numbers = [1, 2, 3] // Number[]

Rules

• element types are inferred from the contents
• mixed arrays produce union element types
• arrays are immutable
• array-transforming operations return new arrays

Example:

values = [1, 'two'] // (Number | String)[]

Comparison to JavaScript

JavaScript arrays are flexible and mutable. FScript arrays are more predictable and friendlier to static reasoning.