heterarchy/lib/heterarchy.js

Cooperative multiple inheritance for CoffeeScript, á-la Python

// Generated by CoffeeScript 1.10.0
(function() {
  var assert, copyOwn, every, find, generate, head, hierarchy, inherited, isEmpty, isEqual, isJavaScriptClass, javaScriptClassNames, javaScriptClasses, map, memoize, merge, mro, partial, reduce, ref, reject, reparent, some, tail, without,
    slice = [].slice,
    extend = function(child, parent) { for (var key in parent) { if (hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; },
    hasProp = {}.hasOwnProperty,
    indexOf = [].indexOf || function(item) { for (var i = 0, l = this.length; i < l; i++) { if (i in this && this[i] === item) return i; } return -1; };

  ref = require('underscore'), head = ref.head, tail = ref.tail, map = ref.map, find = ref.find, some = ref.some, without = ref.without, isEmpty = ref.isEmpty, every = ref.every, memoize = ref.memoize, reject = ref.reject, partial = ref.partial, isEqual = ref.isEqual, reduce = ref.reduce;

  assert = function(value, error) {
    if (!value) {
      throw new Error(error != null ? error : "Assertion failed");
    }
  };

  exports.multi = function() {
    var bases;
    bases = 1 <= arguments.length ? slice.call(arguments, 0) : [];
    return generate(merge(map(bases, mro).concat([bases])));
  };

  generate = memoize(function(linearization) {
    var Result, next;
    next = head(linearization);
    if (isEqual(linearization, hierarchy(next))) {
      return next;
    } else {
      return Result = (function(superClass) {
        var class1;

        extend(Result, superClass);

        function Result() {
          return class1.apply(this, arguments);
        }

        Result.prototype.__mro__ = linearization;

        class1 = reparent(next, Result, next.prototype.constructor);

        copyOwn(next, Result);

        copyOwn(next.prototype, Result.prototype, partial(reparent, next, Result));

        return Result;

      })(generate(tail(linearization)));
    }
  });

  copyOwn = function(from, to, project) {
    var key, value;
    if (project == null) {
      project = function(x) {
        return x;
      };
    }
    for (key in from) {
      if (!hasProp.call(from, key)) continue;
      value = from[key];
      if (!to.hasOwnProperty(key)) {
        to[key] = project(value);
      }
    }
    return to;
  };

  reparent = function(oldklass, newklass, value) {
    var newsuper, oldsuper, superctor;
    if (!(value instanceof Function)) {
      return value;
    } else if (value === oldklass.prototype.constructor && inherited(oldklass) === Object) {
      superctor = inherited(newklass).prototype.constructor;
      return function() {
        superctor.apply(this, arguments);
        return value.apply(this, arguments);
      };
    } else {
      newsuper = inherited(newklass).prototype;
      oldsuper = oldklass.__super__;
      return function() {
        oldklass.__super__ = newsuper;
        try {
          return value.apply(this, arguments);
        } finally {
          oldklass.__super__ = oldsuper;
        }
      };
    }
  };

  merge = function(inputs) {
    var next, results;
    results = [];
    while (!isEmpty(inputs)) {
      next = find(map(inputs, head), function(candidate) {
        return every(inputs, function(input) {
          return indexOf.call(tail(input), candidate) < 0;
        });
      });
      assert(next != null, "Inconsistent multiple inheritance");
      inputs = reject(map(inputs, function(lst) {
        return without(lst, next);
      }), isEmpty);
      results.push(next);
    }
    return results;
  };

  javaScriptClassNames = ["Array", "Boolean", "Date", "Error", "Function", "Number", "RegExp", "String", "Object", "EvalError", "RangeError", "ReferenceError", "SyntaxError", "TypeError", "URIError", "Symbol", "Int8Array", "Uint8Array", "Uint8ClampedArray", "Int16Array", "Uint16Array", "Int32Array", "Uint32Array", "Float32Array", "Float64Array", "Map", "Set", "WeakMap", "WeakSet", "ArrayBuffer", "DataView", "Promise", "Generator", "GeneratorFunction", "Reflect", "Proxy"];

  javaScriptClasses = reduce(javaScriptClassNames, function(classes, name) {
    classes[global[name]] = global[name];
    return classes;
  }, {});

  isJavaScriptClass = function(cls) {
    return javaScriptClasses[cls] === cls;
  };

  exports.mro = mro = function(cls) {
    var result;
    if ((cls == null) || (cls.prototype == null)) {
      return [];
    } else if (!cls.prototype.hasOwnProperty('__mro__')) {
      result = [cls].concat(mro(inherited(cls)));
      if (!isJavaScriptClass(cls)) {
        cls.prototype.__mro__ = result;
      }
      return result;
    } else {
      return cls.prototype.__mro__;
    }
  };

  exports.inherited = inherited = function(cls) {
    var ref1;
    return (ref1 = Object.getPrototypeOf(cls.prototype)) != null ? ref1.constructor : void 0;
  };

  exports.hierarchy = hierarchy = function(cls) {
    if (cls == null) {
      return [];
    } else {
      return [cls].concat(hierarchy(inherited(cls)));
    }
  };

  exports.isinstance = function() {
    var classes, obj;
    obj = arguments[0], classes = 2 <= arguments.length ? slice.call(arguments, 1) : [];
    return exports.issubclass.apply(exports, [obj != null ? obj.constructor : void 0].concat(slice.call(classes)));
  };

  exports.issubclass = function() {
    var classes, klass, linearization;
    klass = arguments[0], classes = 2 <= arguments.length ? slice.call(arguments, 1) : [];
    linearization = mro(klass);
    return some(classes, function(cls) {
      return indexOf.call(linearization, cls) >= 0;
    });
  };

}).call(this);