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Type Alias: Validator()<T>

Validator<T>: (value) => value is T

Defined in: src/types/validation.ts:126

Type guard validator function.

Type Parameters​

• T

Type to validate

Parameters​

value​

unknown

Returns​

value is T

Remarks​

A validator function that returns true if the value is of type T, false otherwise. TypeScript narrows the type when this function returns true.

This is a simple boolean validator. For detailed validation with error messages, use SchemaValidator instead.

Example​

const isPositive: Validator<number> = (value): value is number => {
  return typeof value === 'number' && value > 0;
};

const value: unknown = 5;
if (isPositive(value)) {
  // TypeScript knows value is number here
  console.log(value * 2);
}