/**
 * Module schema provides code to safely handle JSON Typedef schemas.
 *
 * JSON Typedef schemas are represented in this module with {@link Schema}, and
 * you can check if a JSON object is a correct schema by using {@link isSchema}
 * and {@link isValidSchema}.
 *
 * @packageDocumentation
 */
/**
 * Schema is a TypeScript representation of a correct JSON Typedef schema.
 *
 * The JSON Typedef specification allows schemas to take on one of eight forms.
 * Each of those forms has its own type in this module; Schema is simply a union
 * of each of those eight types.
 */
export declare type Schema = SchemaFormEmpty | SchemaFormRef | SchemaFormType | SchemaFormEnum | SchemaFormElements | SchemaFormProperties | SchemaFormValues | SchemaFormDiscriminator;
/**
 * SchemaFormEmpty represents schemas of the empty form.
 */
export declare type SchemaFormEmpty = SharedFormProperties;
/**
 * SchemaFormRef represents schemas of the ref form.
 */
export declare type SchemaFormRef = SharedFormProperties & {
    ref: string;
};
/**
 * SchemaFormType represents schemas of the type form.
 */
export declare type SchemaFormType = SharedFormProperties & {
    type: Type;
};
/**
 * Type represents the legal values of the "type" keyword in JSON Typedef.
 */
export declare type Type = "boolean" | "float32" | "float64" | "int8" | "uint8" | "int16" | "uint16" | "int32" | "uint32" | "string" | "timestamp";
/**
 * SchemaFormEnum represents schemas of the enum form.
 */
export declare type SchemaFormEnum = SharedFormProperties & {
    enum: string[];
};
/**
 * SchemaFormElements represents schemas of the elements form.
 */
export declare type SchemaFormElements = SharedFormProperties & {
    elements: Schema;
};
/**
 * SchemaFormProperties represents schemas of the properties form.
 */
export declare type SchemaFormProperties = SharedFormProperties & ({
    properties?: {
        [name: string]: Schema;
    };
    optionalProperties: {
        [name: string]: Schema;
    };
    additionalProperties?: boolean;
} | {
    properties: {
        [name: string]: Schema;
    };
    optionalProperties?: {
        [name: string]: Schema;
    };
    additionalProperties?: boolean;
});
/**
 * SchemaFormValues represents schemas of the values form.
 */
export declare type SchemaFormValues = SharedFormProperties & {
    values: Schema;
};
/**
 * SchemaFormDiscriminator represents schemas of the discriminator form.
 */
export declare type SchemaFormDiscriminator = SharedFormProperties & {
    discriminator: string;
    mapping: {
        [name: string]: Schema;
    };
};
/**
 * SharedFormProperties contains the properties shared among all schema forms.
 */
interface SharedFormProperties {
    definitions?: {
        [definition: string]: Schema;
    };
    metadata?: {
        [name: string]: unknown;
    };
    nullable?: boolean;
}
/**
 * isEmptyForm checks whether some Schema is of the empty form.
 *
 * @param schema The schema to validate
 */
export declare function isEmptyForm(schema: Schema): schema is SchemaFormEmpty;
/**
 * isRefForm checks whether some Schema is of the ref form.
 *
 * @param schema The schema to validate
 */
export declare function isRefForm(schema: Schema): schema is SchemaFormRef;
/**
 * isTypeForm checks whether some Schema is of the type form.
 *
 * @param schema The schema to validate
 */
export declare function isTypeForm(schema: Schema): schema is SchemaFormType;
/**
 * isEnumForm checks whether some Schema is of the enum form.
 *
 * @param schema The schema to validate
 */
export declare function isEnumForm(schema: Schema): schema is SchemaFormEnum;
/**
 * isElementsForm checks whether some Schema is of the elements form.
 *
 * @param schema The schema to validate
 */
export declare function isElementsForm(schema: Schema): schema is SchemaFormElements;
/**
 * isPropertiesForm checks whether some Schema is of the properties form.
 *
 * @param schema The schema to validate
 */
export declare function isPropertiesForm(schema: Schema): schema is SchemaFormProperties;
/**
 * isPropertiesForm checks whether some Schema is of the values form.
 *
 * @param schema The schema to validate
 */
export declare function isValuesForm(schema: Schema): schema is SchemaFormValues;
/**
 * isDiscriminatorForm checks whether some Schema is of the values form.
 *
 * @param schema The schema to validate
 */
export declare function isDiscriminatorForm(schema: Schema): schema is SchemaFormDiscriminator;
/**
 * isValidSchema checks whether some Schema is correct, according to the syntax
 * rules of JSON Typedef.
 *
 * In particular, isValidSchema verifies that:
 *
 * 1. The schema does not have any non-root definitions,
 * 2. All references point to actually-existing definitions,
 * 3. All enums are non-empty, and do not contain duplicates,
 * 4. The `properties` and `optionalProperties` of a schema never share
 *    properties,
 * 5. All schemas in `mapping` are of the properties form,
 * 6. Schemas in `mapping` never re-specify the `discriminator` property
 *
 * If an object returned from `JSON.parse` passes both {@link isSchema} and
 * {@link isValidSchema}, then it is a correct JSON Typedef schema.
 *
 * @param schema The schema to validate
 * @param root The schema to consider as the "root" schema. If undefined,
 * `schema` will be used as the root. This is usually what you want to do.
 */
export declare function isValidSchema(schema: Schema, root?: Schema): boolean;
/**
 * isSchema checks whether some piece of JSON data has the shape of a JSON
 * Typedef Schema.
 *
 * This function only looks at the "shape" of data: it just makes sure all
 * property names and types are valid, and that the data takes on one of the
 * eight JSON Typedef forms.
 *
 * If an object returned from `JSON.parse` passes both {@link isSchema} and
 * {@link isValidSchema}, then it is a correct JSON Typedef schema.
 *
 * @param data The data to check
 */
export declare function isSchema(data: unknown): data is Schema;
export {};