Typescript Assertion

level: loglevel.LogLevelDesc = <loglevel.LogLevelDesc> level

See Typescript - Type Assertion (angle-bracket or as)

Jsdoc

Typescript borrows cast syntax from Closure. This lets you cast types to other types by adding a @type tag before any parenthesized expression.

/**
 * @type {number | string}
 */
var numberOrString = Math.random() < 0.5 ? "hello" : 100;
var typeAssertedNumber = /** @type {number} */ (numberOrString)

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