assert

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Checks if a condition is true. If the condition is false, it throws an error with a specified message. This function is useful for enforcing runtime invariants and conditions that must hold. It also uses the TypeScript asserts keyword to inform the type checker that the condition is always true after the assertion.

• @param condition - The condition which should be true.
• @param message - The message to throw if the condition is false.
• @param errorType - The type of error to throw if the condition is false.
• @throws Error If the condition is false.

Example

assert(foo !== undefined, 'foo should not be undefined')
assert(typeof bar !== 'string', 'bar should not be of type string')
assert(baz.length > 0', 'baz should have a length greater than 0', RangeError)