Generate all runtime files from dart.

lib/runtime/dart/_rtti.js

-// Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-/* This library defines the association between runtime objects and
- * runtime types.
-*/
-
-dart_library.library('dart/_rtti', null, /* Imports */[
-], /* Lazy Imports */[
-  'dart/_utils',
-  'dart/core',
-  'dart/_types'
-], function(exports, dart_utils, core, types) {
-  'use strict';
-
-  const defineLazyProperty = dart_utils.defineLazyProperty;
-
-  const defineProperty = Object.defineProperty;
-
-  /**
-   * Runtime type information.  This module defines the mapping from
-   * runtime objects to their runtime type information.  See the types
-   * module for the definition of how type information is represented.
-   *
-   * Runtime objects fall into four main categories:
-   *
-   *   - Things represented by javascript primitives, such as
-   *     null, numbers, booleans, strings, and symbols.  For these
-   *     we map directly from the javascript type (given by typeof)
-   *     to the appropriate class type from core, which serves as their
-   *     rtti.
-   *
-   *   - Functions, which are represented by javascript functions.
-   *     Representations of Dart functions always have a
-   *     _runtimeType property attached to them with the appropriate
-   *     rtti.
-   *
-   *   - Objects (instances) which are represented by instances of
-   *     javascript (ES6) classes.  Their types are given by their
-   *     classes, and the rtti is accessed by projecting out their
-   *     constructor field.
-   *
-   *   - Types objects, which are represented as described in the types
-   *     module.  Types always have a _runtimeType property attached to
-   *     them with the appropriate rtti.  The rtti for these is always
-   *     core.Type.  TODO(leafp): consider the possibility that we can
-   *     reliably recognize type objects and map directly to core.Type
-   *     rather than attaching this property everywhere.
-   *
-   */
-
-  /**
-   *Tag a closure with a type, using one of three forms:
-   * dart.fn(cls) marks cls has having no optional or named
-   *  parameters, with all argument and return types as dynamic
-   * dart.fn(cls, func) marks cls with the lazily computed
-   *  runtime type as computed by func()
-   * dart.fn(cls, rType, argsT, extras) marks cls as having the
-   * runtime type dart.functionType(rType, argsT, extras)
-   *
-   * Note that since we are producing a type for a concrete function,
-   * it is sound to use the definite arrow type.
-   */
-  function fn(closure, ...args) {
-    // Closure and a lazy type constructor
-    if (args.length == 1) {
-      defineLazyProperty(closure, _runtimeType, {get : args[0]});
-      return closure;
-    }
-    let t;
-    if (args.length == 0) {
-      // No type arguments, it's all dynamic
-      t = types.definiteFunctionType(
-        types.dynamic, Array(closure.length).fill(types.dynamic));
-    } else {
-      // We're passed the piecewise components of the function type,
-      // construct it.
-      t = types.definiteFunctionType.apply(null, args);
-    }
-    tag(closure, t);
-    return closure;
-  }
-  exports.fn = fn;
-
-  // TODO(vsm): How should we encode the runtime type?
-  const _runtimeType = Symbol('_runtimeType');
-
-  function checkPrimitiveType(obj) {
-    switch (typeof obj) {
-      case "undefined":
-        return core.Null;
-      case "number":
-        return Math.floor(obj) == obj ? core.int : core.double;
-      case "boolean":
-        return core.bool;
-      case "string":
-        return core.String;
-      case "symbol":
-        return Symbol;
-    }
-    // Undefined is handled above. For historical reasons,
-    // typeof null == "object" in JS.
-    if (obj === null) return core.Null;
-    return null;
-  }
-
-  function runtimeType(obj) {
-    let result = checkPrimitiveType(obj);
-    if (result !== null) return result;
-    return obj.runtimeType;
-  }
-  exports.runtimeType = runtimeType;
-
-  function getFunctionType(obj) {
-    // TODO(vsm): Encode this properly on the function for Dart-generated code.
-    let args = Array(obj.length).fill(types.dynamic);
-    return types.definiteFunctionType(types.bottom, args);
-  }
-
-  /**
-   * Returns the runtime type of obj. This is the same as `obj.realRuntimeType`
-   * but will not call an overridden getter.
-   *
-   * Currently this will return null for non-Dart objects.
-   */
-  function realRuntimeType(obj) {
-    let result = checkPrimitiveType(obj);
-    if (result !== null) return result;
-    // TODO(vsm): Should we treat Dart and JS objects differently here?
-    // E.g., we can check if obj instanceof core.Object to differentiate.
-    result = obj[_runtimeType];
-    if (result) return result;
-    result = obj.constructor;
-    if (result == Function) {
-      // An undecorated Function should have come from
-      // JavaScript.  Treat as untyped.
-      return types.jsobject;
-    }
-    return result;
-  }
-  exports.realRuntimeType = realRuntimeType;
-
-  function LazyTagged(infoFn) {
-    class _Tagged {
-      get [_runtimeType]() {return infoFn();}
-    }
-    return _Tagged;
-  }
-  exports.LazyTagged = LazyTagged;
-
-  function read(value) {
-    return value[_runtimeType];
-  }
-  exports.read = read;
-
-  function tag(value, info) {
-    value[_runtimeType] = info;
-  }
-  exports.tag = tag;
-
-  function tagComputed(value, compute) {
-    defineProperty(value, _runtimeType, { get: compute });
-  }
-  exports.tagComputed = tagComputed;
-
-  function tagMemoized(value, compute) {
-    let cache = null;
-    function getter() {
-      if (compute == null) return cache;
-      cache = compute();
-      compute = null;
-      return cache;
-    }
-    tagComputed(value, getter);
-  }
-  exports.tagMemoized = tagMemoized;
-});