/**
 * A runtime checker that ensures a given value is set (i.e. not undefined or null)
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 */
export declare function jCheckSet<T>(value: T): T;
/**
 * A runtime checker that ensures a given value is a boolean
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 * This implies jCheckSet.
 */
export declare function jCheckBoolean(value: boolean): boolean;
/**
 * A runtime checker that ensures a given value is a string.
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 * This implies jCheckSet.
 */
export declare function jCheckString(value: string): string;
/**
 * A runtime checker that ensures a given value is a number
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 * This implies jCheckSet.
 */
export declare function jCheckNumber(value: number): number;
/**
 * A runtime checker that ensures a given value is an array
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 * This implies jCheckSet.
 */
export declare function jCheckArray<T>(value: readonly T[]): readonly T[];
/**
 * A runtime checker that ensures a given value is an object in the sense of JSON
 * (an unordered collection of key–value pairs where the keys are strings)
 *
 * This is used when you want to verify that data at runtime matches the expected type.
 * This implies jCheckSet.
 */
export declare function jCheckObject<T>(value: T): T;
/**
 * Throws an error if value is not a string or is empty.
 *
 * Otherwise returns the value.
 *
 * This implies jCheckString.
 */
export declare function jCheckNonEmptyString(value: string): string;
/**
 * Throws an error if value is not a string or is empty.
 *
 * Otherwise returns the value.
 *
 * This implies jCheckNumber.
 */
export declare function jCheckNonZeroNumber(value: number): number;