123456789101112131415161718192021222324
import { Key, Values } from "../libs/types.ts";import { RULE, ValueSchemaError } from "../libs/ValueSchemaError.ts";export interface Rules<T> {    /** value if null (defaults: error) */    ifNull?: T | null;}/** * apply schema * @param values input/output values * @param rules rules * @param keyStack key stack for error handling * @returns escapes from applyTo chain or not */export function applyTo<T>(values: Values, rules: Rules<T>, keyStack: Key[]): values is Values<T> {    if (values.output !== null) {        return false;    }    if (rules.ifNull !== undefined) {        values.output = rules.ifNull;        return true;    }    return ValueSchemaError.raise(RULE.NULL, values, keyStack);}