added and= and or= to the language.

src/nodes.coffee

@@ -112,7 +112,7 @@ exports.BaseNode = class BaseNode
   # `toString` representation of the node, for inspecting the parse tree.
   # This is what `coffee --nodes` prints out.
   toString: (idt, override) ->
-    idt ||= ''
+    idt or= ''
     children = (child.toString idt + TAB for child in @collectChildren()).join('')
     '\n' + idt + (override or @class) + children
 
@@ -193,7 +193,7 @@ exports.Expressions = class Expressions extends BaseNode
 
   # An **Expressions** is the only node that can serve as the root.
   compile: (o) ->
-    o ||= {}
+    o or= {}
     if o.scope then super(o) else @compileRoot(o)
 
   compileNode: (o) ->
@@ -354,7 +354,7 @@ exports.ValueNode = class ValueNode extends BaseNode
     only        = del o, 'onlyFirst'
     op          = del o, 'operation'
     props       = if only then @properties[0...@properties.length - 1] else @properties
-    o.chainRoot ||= this
+    o.chainRoot or= this
     baseline    = @base.compile o
     baseline    = "($baseline)" if @hasProperties() and (@base instanceof ObjectNode or @isNumber())
     complete    = @last = baseline
@@ -502,7 +502,7 @@ exports.AccessorNode = class AccessorNode extends BaseNode
 
   compileNode: (o) ->
     name = @name.compile o
-    o.chainRoot.wrapped ||= @soakNode
+    o.chainRoot.wrapped or= @soakNode
     namePart = if name.match(IS_STRING) then "[$name]" else ".$name"
     @prototype + namePart
 
@@ -518,7 +518,7 @@ exports.IndexNode = class IndexNode extends BaseNode
     @index = index
 
   compileNode: (o) ->
-    o.chainRoot.wrapped ||= @soakNode
+    o.chainRoot.wrapped or= @soakNode
     idx = @index.compile o
     prefix = if @proto then '.prototype' else ''
     "$prefix[$idx]"
@@ -570,7 +570,7 @@ exports.RangeNode = class RangeNode extends BaseNode
     [from, to] = [parseInt(@fromNum, 10), parseInt(@toNum, 10)]
     idx        = del o, 'index'
     step       = del o, 'step'
-    step       &&= "$idx += ${step.compile(o)}"
+    step       and= "$idx += ${step.compile(o)}"
     if from <= to
       "$idx = $from; $idx <$@equals $to; ${step or "$idx++"}"
     else
@@ -721,8 +721,8 @@ exports.ClassNode = class ClassNode extends BaseNode
         continue
       if func instanceof CodeNode and func.bound
         func.bound = false
-        constScope ||= new Scope(o.scope, constructor.body, constructor)
-        me ||= constScope.freeVariable()
+        constScope or= new Scope(o.scope, constructor.body, constructor)
+        me or= constScope.freeVariable()
         pname = pvar.compile(o)
         constructor.body.push    new ReturnNode literal 'this' if constructor.body.empty()
         constructor.body.unshift literal "this.${pname} = function(){ return ${className}.prototype.${pname}.apply($me, arguments); }"
@@ -902,7 +902,7 @@ exports.CodeNode = class CodeNode extends BaseNode
   traverseChildren: (crossScope, func) -> super(crossScope, func) if crossScope
 
   toString: (idt) ->
-    idt ||= ''
+    idt or= ''
     children = (child.toString(idt + TAB) for child in @collectChildren()).join('')
     "\n$idt$children"
 
@@ -1385,7 +1385,7 @@ exports.IfNode = class IfNode extends BaseNode
   # The **IfNode** only compiles into a statement if either of its bodies needs
   # to be a statement. Otherwise a ternary is safe.
   isStatement: ->
-    @statement ||= !!(@tags.statement or @bodyNode().isStatement() or (@elseBody and @elseBodyNode().isStatement()))
+    @statement or= !!(@tags.statement or @bodyNode().isStatement() or (@elseBody and @elseBodyNode().isStatement()))
 
   compileCondition: (o) ->
     (cond.compile(o) for cond in flatten([@condition])).join(' || ')
@@ -1395,8 +1395,8 @@ exports.IfNode = class IfNode extends BaseNode
 
   makeReturn: ->
     if @isStatement()
-      @body     &&= @ensureExpressions(@body.makeReturn())
-      @elseBody &&= @ensureExpressions(@elseBody.makeReturn())
+      @body     and= @ensureExpressions(@body.makeReturn())
+      @elseBody and= @ensureExpressions(@elseBody.makeReturn())
       this
     else
       new ReturnNode this