jashkenas--coffeescript/lib/coffee_script/nodes.js

(function(){
  var AccessorNode, CallNode, CommentNode, Expressions, ExtendsNode, IndexNode, LiteralNode, Node, ReturnNode, TAB, TRAILING_WHITESPACE, ThisNode, ValueNode, any, compact, del, dup, flatten, inherit, merge, statement;
  var __hasProp = Object.prototype.hasOwnProperty;
  process.mixin(require('./scope'));
  // The abstract base class for all CoffeeScript nodes.
  // All nodes are implement a "compile_node" method, which performs the
  // code generation for that node. To compile a node, call the "compile"
  // method, which wraps "compile_node" in some extra smarts, to know when the
  // generated code should be wrapped up in a closure. An options hash is passed
  // and cloned throughout, containing messages from higher in the AST,
  // information about the current scope, and indentation level.
  exports.Expressions = function Expressions() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.LiteralNode = function LiteralNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ReturnNode = function ReturnNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.CommentNode = function CommentNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.CallNode = function CallNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ExtendsNode = function ExtendsNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ValueNode = function ValueNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.AccessorNode = function AccessorNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.IndexNode = function IndexNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.RangeNode = function RangeNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.SliceNode = function SliceNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ThisNode = function ThisNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.AssignNode = function AssignNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.OpNode = function OpNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.CodeNode = function CodeNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.SplatNode = function SplatNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ObjectNode = function ObjectNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ArrayNode = function ArrayNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.PushNode = function PushNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ClosureNode = function ClosureNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.WhileNode = function WhileNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ForNode = function ForNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.TryNode = function TryNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ThrowNode = function ThrowNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ExistenceNode = function ExistenceNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.ParentheticalNode = function ParentheticalNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.IfNode = function IfNode() {
    var arguments = Array.prototype.slice.call(arguments, 0);
    this.name = this.constructor.name;
    return this.values = arguments;
  };
  exports.Expressions.wrap = function wrap(values) {
    return this.values = values;
  };
  // Some helper functions
  // Tabs are two spaces for pretty printing.
  TAB = '  ';
  TRAILING_WHITESPACE = /\s+$/g;
  // Flatten nested arrays recursively.
  flatten = function flatten(list) {
    var __a, __b, item, memo;
    memo = [];
    __a = list;
    for (__b = 0; __b < __a.length; __b++) {
      item = __a[__b];
      if (item instanceof Array) {
        return memo.concat(flatten(item));
      }
      memo.push(item);
      memo;
    }
    return memo;
  };
  // Remove all null values from an array.
  compact = function compact(input) {
    var __a, __b, __c, item;
    __a = []; __b = input;
    for (__c = 0; __c < __b.length; __c++) {
      item = __b[__c];
      if ((typeof item !== "undefined" && item !== null)) {
        __a.push(item);
      }
    }
    return __a;
  };
  // Dup an array or object.
  dup = function dup(input) {
    var __a, __b, __c, __d, key, output, val;
    if (input instanceof Array) {
      __a = []; __b = input;
      for (__c = 0; __c < __b.length; __c++) {
        val = __b[__c];
        __a.push(val);
      }
      return __a;
    } else {
      output = {
      };
      __d = input;
      for (key in __d) {
        val = __d[key];
        if (__hasProp.call(__d, key)) {
          ((output[key] = val));
        }
      }
      return output;
    }
  };
  // Merge objects.
  merge = function merge(src, dest) {
    var __a, key, val;
    __a = src;
    for (key in __a) {
      val = __a[key];
      if (__hasProp.call(__a, key)) {
        ((dest[key] = val));
      }
    }
    return dest;
  };
  // Do any of the elements in the list pass a truth test?
  any = function any(list, test) {
    var __a, __b, __c, item, result;
    result = (function() {
      __a = []; __b = list;
      for (__c = 0; __c < __b.length; __c++) {
        item = __b[__c];
        if (test(item)) {
          __a.push(true);
        }
      }
      return __a;
    }).call(this);
    return !!result.length;
  };
  // Delete a key from an object, returning the value.
  del = function del(obj, key) {
    var val;
    val = obj[key];
    delete obj[key];
    return val;
  };
  // Quickie inheritance convenience wrapper to reduce typing.
  inherit = function inherit(parent, props) {
    var __a, __b, klass, name, prop;
    klass = del(props, 'constructor');
    __a = function(){};
    __a.prototype = parent.prototype;
    klass.__superClass__ = parent.prototype;
    klass.prototype = new __a();
    klass.prototype.constructor = klass;
    __b = props;
    for (name in __b) {
      prop = __b[name];
      if (__hasProp.call(__b, name)) {
        ((klass.prototype[name] = prop));
      }
    }
    return klass;
  };
  // # Provide a quick implementation of a children method.
  // children: (klass, attrs...) ->
  //   klass::children: ->
  //     nodes: this[attr] for attr in attrs
  //     compact flatten nodes
  // Mark a node as a statement, or a statement only.
  statement = function statement(klass, only) {
    klass.prototype.is_statement = function is_statement() {
      return true;
    };
    if (only) {
      return ((klass.prototype.is_statement_only = function is_statement_only() {
        return true;
      }));
    }
  };
  // The abstract base class for all CoffeeScript nodes.
  // All nodes are implement a "compile_node" method, which performs the
  // code generation for that node. To compile a node, call the "compile"
  // method, which wraps "compile_node" in some extra smarts, to know when the
  // generated code should be wrapped up in a closure. An options hash is passed
  // and cloned throughout, containing messages from higher in the AST,
  // information about the current scope, and indentation level.
  Node = (exports.Node = function Node() {  });
  // This is extremely important -- we convert JS statements into expressions
  // by wrapping them in a closure, only if it's possible, and we're not at
  // the top level of a block (which would be unnecessary), and we haven't
  // already been asked to return the result.
  Node.prototype.compile = function compile(o) {
    var closure, top;
    this.options = dup(o || {
    });
    this.indent = o.indent;
    top = this.top_sensitive() ? o.top : del(o, 'top');
    closure = this.is_statement() && !this.is_statement_only() && !top && !o.returns && !this instanceof CommentNode && !this.contains(function(node) {
      return node.is_statement_only();
    });
    return closure ? this.compile_closure(this.options) : this.compile_node(this.options);
  };
  // Statements converted into expressions share scope with their parent
  // closure, to preserve JavaScript-style lexical scope.
  Node.prototype.compile_closure = function compile_closure(o) {
    this.indent = o.indent;
    o.shared_scope = o.scope;
    return ClosureNode.wrap(this).compile(o);
  };
  // Quick short method for the current indentation level, plus tabbing in.
  Node.prototype.idt = function idt(tabs) {
    var __a, __b, __c, __d, i, idt;
    idt = (this.indent || '');
    __c = 0; __d = (tabs || 0);
    for (__b=0, i=__c; (__c <= __d ? i < __d : i > __d); (__c <= __d ? i += 1 : i -= 1), __b++) {
      idt += TAB;
    }
    return idt;
  };
  // Does this node, or any of its children, contain a node of a certain kind?
  Node.prototype.contains = function contains(block) {
    var __a, __b, node;
    __a = this.children;
    for (__b = 0; __b < __a.length; __b++) {
      node = __a[__b];
      if (block(node)) {
        return true;
      }
      if (node instanceof Node && node.contains(block)) {
        return true;
      }
    }
    return false;
  };
  // Default implementations of the common node methods.
  Node.prototype.unwrap = function unwrap() {
    return this;
  };
  Node.prototype.children = [];
  Node.prototype.is_statement = function is_statement() {
    return false;
  };
  Node.prototype.is_statement_only = function is_statement_only() {
    return false;
  };
  Node.prototype.top_sensitive = function top_sensitive() {
    return false;
  };
  // A collection of nodes, each one representing an expression.
  Expressions = (exports.Expressions = inherit(Node, {
    constructor: function constructor(nodes) {
      this.expressions = flatten(nodes);
      this.children = this.expressions;
      return this;
    },
    // Tack an expression on to the end of this expression list.
    push: function push(node) {
      this.expressions.push(node);
      return this;
    },
    // Tack an expression on to the beginning of this expression list.
    unshift: function unshift(node) {
      this.expressions.unshift(node);
      return this;
    },
    // If this Expressions consists of a single node, pull it back out.
    unwrap: function unwrap() {
      return this.expressions.length === 1 ? this.expressions[0] : this;
    },
    // Is this an empty block of code?
    empty: function empty() {
      return this.expressions.length === 0;
    },
    // Is the node last in this block of expressions?
    is_last: function is_last(node) {
      var l;
      l = this.expressions.length;
      this.last_index = this.last_index || this.expressions[l - 1] instanceof CommentNode ? -2 : -1;
      return node === this.expressions[l - this.last_index];
    },
    compile: function compile(o) {
      o = o || {
      };
      return o.scope ? compile.__superClass__.constructor.call(this, o) : this.compile_root(o);
    },
    // Compile each expression in the Expressions body.
    compile_node: function compile_node(o) {
      var __a, __b, __c, node;
      return ((function() {
        __a = []; __b = this.expressions;
        for (__c = 0; __c < __b.length; __c++) {
          node = __b[__c];
          __a.push(this.compile_expression(node, dup(o)));
        }
        return __a;
      }).call(this)).join("\n");
    },
    // If this is the top-level Expressions, wrap everything in a safety closure.
    compile_root: function compile_root(o) {
      var code, indent;
      o.indent = (this.indent = (indent = o.no_wrap ? '' : TAB));
      o.scope = new Scope(null, this, null);
      code = o.globals ? this.compile_node(o) : this.compile_with_declarations(o);
      code = code.replace(TRAILING_WHITESPACE, '');
      return o.no_wrap ? code : "(function(){\n" + code + "\n})();";
    },
    // Compile the expressions body, with declarations of all inner variables
    // pushed up to the top.
    compile_with_declarations: function compile_with_declarations(o) {
      var args, argv, code;
      code = this.compile_node(o);
      args = this.contains(function(node) {
        return node instanceof ValueNode && node.is_arguments();
      });
      argv = args && o.scope.check('arguments') ? '' : 'var ';
      if (args) {
        code = this.idt() + argv + "arguments = Array.prototype.slice.call(arguments, 0);\n" + code;
      }
      if (o.scope.has_assignments(this)) {
        code = this.idt() + 'var ' + o.scope.compiled_assignments() + ";\n" + code;
      }
      if (o.scope.has_declarations(this)) {
        code = this.idt() + 'var ' + o.scope.compiled_declarations() + ";\n" + code;
      }
      return code;
    },
    // Compiles a single expression within the expressions body.
    compile_expression: function compile_expression(node, o) {
      var returns, stmt;
      this.indent = o.indent;
      stmt = node.is_statement();
      // We need to return the result if this is the last node in the expressions body.
      returns = del(o, 'returns') && this.is_last(node) && !node.is_statement_only();
      // Return the regular compile of the node, unless we need to return the result.
      if (!(returns)) {
        return (stmt ? '' : this.idt()) + node.compile(merge(o, {
          top: true
        })) + (stmt ? '' : ';');
      }
      // If it's a statement, the node knows how to return itself.
      if (node.is_statement()) {
        return node.compile(merge(o, {
          returns: true
        }));
      }
      // Otherwise, we can just return the value of the expression.
      return this.idt() + 'return ' + node.compile(o);
    }
  }));
  // Wrap up a node as an Expressions, unless it already is one.
  Expressions.wrap = function wrap(nodes) {
    if (nodes.length === 1 && nodes[0] instanceof Expressions) {
      return nodes[0];
    }
    return new Expressions(nodes);
  };
  statement(Expressions);
  // Literals are static values that can be passed through directly into
  // JavaScript without translation, eg.: strings, numbers, true, false, null...
  LiteralNode = (exports.LiteralNode = inherit(Node, {
    constructor: function constructor(value) {
      this.value = value;
      this.children = [value];
      return this;
    },
    // Break and continue must be treated as statements -- they lose their meaning
    // when wrapped in a closure.
    is_statement: function is_statement() {
      return this.value === 'break' || this.value === 'continue';
    },
    compile_node: function compile_node(o) {
      var end, idt;
      idt = this.is_statement() ? this.idt() : '';
      end = this.is_statement() ? ';' : '';
      return idt + this.value + end;
    }
  }));
  LiteralNode.prototype.is_statement_only = LiteralNode.prototype.is_statement;
  // Return an expression, or wrap it in a closure and return it.
  ReturnNode = (exports.ReturnNode = inherit(Node, {
    constructor: function constructor(expression) {
      this.expression = expression;
      this.children = [expression];
      return this;
    },
    compile_node: function compile_node(o) {
      if (this.expression.is_statement()) {
        return this.expression.compile(merge(o, {
          returns: true
        }));
      }
      return this.idt() + 'return ' + this.expression.compile(o) + ';';
    }
  }));
  statement(ReturnNode, true);
  // A value, indexed or dotted into, or vanilla.
  ValueNode = (exports.ValueNode = inherit(Node, {
    SOAK: " == undefined ? undefined : ",
    constructor: function constructor(base, properties) {
      this.base = base;
      this.properties = flatten(properties || []);
      this.children = flatten(this.base, this.properties);
      return this;
    },
    push: function push(prop) {
      this.properties.push(prop);
      this.children.push(prop);
      return this;
    },
    has_properties: function has_properties() {
      return this.properties.length || this.base instanceof ThisNode;
    },
    is_array: function is_array() {
      return this.base instanceof ArrayNode && !this.has_properties();
    },
    is_object: function is_object() {
      return this.base instanceof ObjectNode && !this.has_properties();
    },
    is_splice: function is_splice() {
      return this.has_properties() && this.properties[this.properties.length - 1] instanceof SliceNode;
    },
    is_arguments: function is_arguments() {
      return this.base === 'arguments';
    },
    unwrap: function unwrap() {
      return this.properties.length ? this : this.base;
    },
    // Values are statements if their base is a statement.
    is_statement: function is_statement() {
      return this.base.is_statement && this.base.is_statement() && !this.has_properties();
    },
    compile_node: function compile_node(o) {
      var __a, __b, baseline, code, only, part, parts, prop, props, soaked, temp;
      soaked = false;
      only = del(o, 'only_first');
      props = only ? this.properties.slice(0, this.properties.length) : this.properties;
      baseline = this.base.compile(o);
      parts = [baseline];
      __a = props;
      for (__b = 0; __b < __a.length; __b++) {
        prop = __a[__b];
        if (prop instanceof AccessorNode && prop.soak) {
          soaked = true;
          if (this.base instanceof CallNode && prop === props[0]) {
            temp = o.scope.free_variable();
            parts[parts.length - 1] = '(' + temp + ' = ' + baseline + ')' + this.SOAK + ((baseline = temp + prop.compile(o)));
          } else {
            parts[parts.length - 1] = this.SOAK + (baseline += prop.compile(o));
          }
        } else {
          part = prop.compile(o);
          baseline += part;
          parts.push(part);
        }
      }
      this.last = parts[parts.length - 1];
      this.source = parts.length > 1 ? parts.slice(0, parts.length).join('') : null;
      code = parts.join('').replace(/\)\(\)\)/, '()))');
      if (!(soaked)) {
        return code;
      }
      return '(' + code + ')';
    }
  }));
  // Pass through CoffeeScript comments into JavaScript comments at the
  // same position.
  CommentNode = (exports.CommentNode = inherit(Node, {
    constructor: function constructor(lines) {
      this.lines = lines;
      return this;
    },
    compile_node: function compile_node(o) {
      var delimiter;
      delimiter = "\n" + this.idt() + '//';
      return delimiter + this.lines.join(delimiter);
    }
  }));
  statement(CommentNode);
  // Node for a function invocation. Takes care of converting super() calls into
  // calls against the prototype's function of the same name.
  CallNode = (exports.CallNode = inherit(Node, {
    constructor: function constructor(variable, args) {
      this.variable = variable;
      this.args = args || [];
      this.children = flatten([this.variable, this.args]);
      this.prefix = '';
      return this;
    },
    new_instance: function new_instance() {
      this.prefix = 'new ';
      return this;
    },
    push: function push(arg) {
      this.args.push(arg);
      this.children.push(arg);
      return this;
    },
    // Compile a vanilla function call.
    compile_node: function compile_node(o) {
      var __a, __b, __c, arg, args;
      if (any(this.args, function(a) {
        return a instanceof SplatNode;
      })) {
        return this.compile_splat(o);
      }
      args = ((function() {
        __a = []; __b = this.args;
        for (__c = 0; __c < __b.length; __c++) {
          arg = __b[__c];
          __a.push(arg.compile(o));
        }
        return __a;
      }).call(this)).join(', ');
      if (this.variable === 'super') {
        return this.compile_super(args, o);
      }
      return this.prefix + this.variable.compile(o) + '(' + args + ')';
    },
    // Compile a call against the superclass's implementation of the current function.
    compile_super: function compile_super(args, o) {
      var arg_part, meth, methname;
      methname = o.scope.method.name;
      arg_part = args.length ? ', ' + args : '';
      meth = o.scope.method.proto ? o.scope.method.proto + '.__superClass__.' + methname : methname + '.__superClass__.constructor';
      return meth + '.call(this' + arg_part + ')';
    },
    // Compile a function call being passed variable arguments.
    compile_splat: function compile_splat(o) {
      var __a, __b, arg, args, code, i, meth, obj;
      meth = this.variable.compile(o);
      obj = this.variable.source || 'this';
      args = (function() {
        __a = []; __b = this.args;
        for (i = 0; i < __b.length; i++) {
          arg = __b[i];
          __a.push((function() {
            code = arg.compile(o);
            code = arg instanceof SplatNode ? code : '[' + code + ']';
            return i === 0 ? code : '.concat(' + code + ')';
          }).call(this));
        }
        return __a;
      }).call(this);
      return this.prefix + meth + '.apply(' + obj + ', ' + args.join('') + ')';
    },
    // If the code generation wished to use the result of a function call
    // in multiple places, ensure that the function is only ever called once.
    compile_reference: function compile_reference(o) {
      var call, reference;
      reference = o.scope.free_variable();
      call = new ParentheticalNode(new AssignNode(reference, this));
      return [call, reference];
    }
  }));
  // Node to extend an object's prototype with an ancestor object.
  // After goog.inherits from the Closure Library.
  ExtendsNode = (exports.ExtendsNode = inherit(Node, {
    constructor: function constructor(child, parent) {
      this.child = child;
      this.parent = parent;
      this.children = [child, parent];
      return this;
    },
    // Hooking one constructor into another's prototype chain.
    compile_node: function compile_node(o) {
      var child, constructor, parent;
      constructor = o.scope.free_variable();
      child = this.child.compile(o);
      parent = this.parent.compile(o);
      return this.idt() + constructor + ' = function(){};\n' + this.idt() + constructor + '.prototype = ' + parent + ".prototype;\n" + this.idt() + child + '.__superClass__ = ' + parent + ".prototype;\n" + this.idt() + child + '.prototype = new ' + constructor + "();\n" + this.idt() + child + '.prototype.constructor = ' + child + ';';
    }
  }));
  statement(ExtendsNode);
  // A dotted accessor into a part of a value, or the :: shorthand for
  // an accessor into the object's prototype.
  AccessorNode = (exports.AccessorNode = inherit(Node, {
    constructor: function constructor(name, tag) {
      this.name = name;
      this.children = [this.name];
      this.prototype = tag === 'prototype';
      this.soak = tag === 'soak';
      return this;
    },
    compile_node: function compile_node(o) {
      return '.' + (this.prototype ? 'prototype.' : '') + this.name.compile(o);
    }
  }));
  // An indexed accessor into a part of an array or object.
  IndexNode = (exports.IndexNode = inherit(Node, {
    constructor: function constructor(index) {
      this.children = [(this.index = index)];
      return this;
    },
    compile_node: function compile_node(o) {
      return '[' + this.index.compile(o) + ']';
    }
  }));
  // A this-reference, using '@'.
  ThisNode = (exports.ThisNode = inherit(Node, {
    constructor: function constructor(property) {
      return this.property = property || null;
    },
    compile_node: function compile_node(o) {
      return 'this' + (this.property ? '.' + this.property : '');
    }
  }));
})();