typescript/no-non-null-assertion Restriction
What it does
Disallow non-null assertions using the ! postfix operator.
Why is this bad?
TypeScript's ! non-null assertion operator asserts to the type system that an expression is non-nullable, as in not null or undefined. Using assertions to tell the type system new information is often a sign that code is not fully type-safe. It's generally better to structure program logic so that TypeScript understands when values may be nullable.
Examples
Examples of incorrect code for this rule:
ts
x!;
x!.y;
x.y!;Examples of correct code for this rule:
ts
x;
x?.y;
x.y;How to use
To enable this rule in the CLI or using the config file, you can use:
bash
oxlint --deny typescript/no-non-null-assertionjson
{
"rules": {
"typescript/no-non-null-assertion": "error"
}
}