The course is part of this learning path
This module will introduce you to Simple Types in TypeScript. You’ll learn about Arrays, Tuples, and Type Assertion, too.
The objectives of this module are to provide you with an understanding of:
- What Simple Types are
- How to use Arrays
- How to use Tuples
- How to use Type Assertion
This learning path is aimed at all who wish to learn how to use TypeScript.
We welcome all feedback and suggestions - please contact us at firstname.lastname@example.org to let us know what you think.
Sometimes as developers, we need to override the compiler errors. This is usually when an entity is more specific than its current type suggests. And we need access to its specific types, properties or functions. TypeScript provides us with two syntaxes to do this. The first is angle-bracket syntax. In this example, we have defined thing as any. Provided a value of type string. Unless we tell TypeScript, that thing is a string, it will not let us have access to properties and functions associated with the string type like length. Instead giving us an error. To do this, replace the variable or object and property in parentheses, and we put the type we wish, to assert on it in angle brackets before it. After the closing parentheses, we access the property or function. The second and probably the most common way to do type assertion, is the as-syntax. It follows the same pattern but uses the variable name followed by, as. And then the type to assert. If you use TypeScript in React, you have to use the second method. That now rounds up the module on types and their syntax. Don't forget to get some practice using the labs.