Type Argument Constraints
Explore how to use type argument constraints in TypeScript generics to enforce specific type restrictions inside functions. Understand how to apply the extends keyword and the keyof operator to improve type safety and catch errors at compile time. This lesson helps you write more robust generic functions by restricting permissible type arguments.
We'll cover the following...
We'll cover the following...
Overview
Sometimes it makes sense to put some restrictions on type arguments. Having these restrictions allows you to make assumptions about the type argument when referring to it inside some function.
You can express the restriction using the extends keyword. For example, you might decide to enforce the fact that FormField should only contain string, number, or boolean values.
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