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/**

* Coercions for reading a single value out of an untyped payload — the scalar

* counterparts to {@link toRecord} and {@link toArray} in `./object`. Each

* returns the value when it is already of that type and `null` otherwise, so a

* malformed field reads as absent rather than throwing at the read site.

/** Returns {@link value} when it is a string, `null` otherwise. */

export function toStringOrNull(value: unknown): string | null {

return typeof value === 'string' ? value : null

}

/**

* Returns {@link value} when it is a number, `null` otherwise.

* @remarks Deliberately a `typeof` test only: `NaN` and the infinities are

* numbers and pass through. Callers that need a finite value should say so.

export function toNumberOrNull(value: unknown): number | null {

return typeof value === 'number' ? value : null

}

/** Returns {@link value} when it is a boolean, `null` otherwise. */

export function toBooleanOrNull(value: unknown): boolean | null {

return typeof value === 'boolean' ? value : null

}