November 2019
Beginner
804 pages
20h 1m
English
Content preview from Learn TypeScript 3 by Building Web Applications
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Custom types
One thing that we haven't shown yet is that in TypeScript, you can define custom types.
In TypeScript, as we have already mentioned a few times, type checking is structural; it is strongly tied with the shape of the objects that are considered. When you define the type of an element (for example, variable, field/property, function argument, or function return type), you can use primitive types, classes, interfaces, or custom types.
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