removing the last traces of half-assignments. Issue #541.

documentation/coffee/conditionals.coffee

@@ -8,4 +8,4 @@ else
 
 date = if friday then sue else jill
 
-options = or defaults
+options or= defaults

examples/code.coffee

@@ -60,8 +60,8 @@ race = ->
   race()
 
 # Conditional assignment:
-good = or evil
+good or= evil
-wine = and cheese
+wine and= cheese
 
 # Nested property access and calls.
 ((moon.turn(360))).shapes[3].move({x: 45, y: 30}).position['top'].offset('x')

examples/computer_science/linked_list.coffee

@@ -12,7 +12,7 @@ class LinkedList
     # Create a new node object to wrap the data.
     node = data: data, next: null
 
-    current = this._head = or node
+    current = this._head or= node
 
     if this._head isnt node
       (current = current.next) while current.next

examples/poignant.coffee

@@ -46,7 +46,7 @@ LotteryDraw =
       ticket_list.each (ticket) ->
         score = ticket.score result
         return if score is 0
-        winners[buyer] = or []
+        winners[buyer] or= []
         winners[buyer].push [ticket, score]
     this.tickets = {}
     winners

lib/lexer.js

@@ -70,7 +70,7 @@
       return this.literalToken();
     };
     Lexer.prototype.identifierToken = function() {
-      var _d, close_index, forcedIdentifier, id, tag;
+      var close_index, forcedIdentifier, id, tag;
       if (!(id = this.match(IDENTIFIER, 1))) {
         return false;
       }
@@ -86,9 +86,6 @@
       if (id === 'all' && this.tag() === 'FOR') {
         tag = 'ALL';
       }
-      if (('AND' === (_d = this.tag() === '=' && tag) || 'OR' === _d)) {
-        return this.tag(1, CONVERSIONS[id] + '=');
-      }
       if (include(JS_FORBIDDEN, id)) {
         if (forcedIdentifier) {
           tag = 'STRING';

src/coffee-script.coffee

@@ -30,7 +30,7 @@ lexer = new Lexer
 # Compile a string of CoffeeScript code to JavaScript, using the Coffee/Jison
 # compiler.
 exports.compile = compile = (code, options) ->
-  options = or {}
+  options or= {}
   try
     (parser.parse lexer.tokenize code).compile options
   catch err

src/command.coffee

@@ -156,7 +156,7 @@ printTokens = (tokens) ->
 parseOptions = ->
   optionParser    = new optparse.OptionParser SWITCHES, BANNER
   o = options     = optionParser.parse(process.argv[2...process.argv.length])
-  options.compile = or  !!o.output
+  options.compile or=  !!o.output
   options.run     = not (o.compile or o.print or o.lint)
   options.print   = !!  (o.print or (o.eval or o.stdio and o.compile))
   sources         = options.arguments

src/lexer.coffee

@@ -88,8 +88,6 @@ exports.Lexer = class Lexer
     tag = id.toUpperCase() if include(JS_KEYWORDS, id) or (not forcedIdentifier and include(COFFEE_KEYWORDS, id))
     tag = 'LEADING_WHEN'   if tag is 'WHEN' and include LINE_BREAK, @tag()
     tag = 'ALL'            if id is 'all' and @tag() is 'FOR'
-    if @tag() is '=' and tag in ['AND', 'OR']
-      return @tag 1, CONVERSIONS[id] + '='
     if include(JS_FORBIDDEN, id)
       if forcedIdentifier
         tag = 'STRING'
@@ -259,7 +257,7 @@ exports.Lexer = class Lexer
     value = match and match[1]
     space = match and match[2]
     @tagParameters() if value and value.match CODE
-    value = or @chunk.substr 0, 1
+    value or= @chunk.substr 0, 1
     @i += value.length
     prevSpaced = @prev() and @prev().spaced
     tag = value
@@ -347,7 +345,7 @@ exports.Lexer = class Lexer
   # contents of the string. This method allows us to have strings within
   # interpolations within strings, ad infinitum.
   balancedString: (str, delimited, options) ->
-    options = or {}
+    options or= {}
     slash = delimited[0][0] is '/'
     levels = []
     i = 0
@@ -384,7 +382,7 @@ exports.Lexer = class Lexer
   # new Lexer, tokenize the interpolated contents, and merge them into the
   # token stream.
   interpolateString: (str, options) ->
-    options = or {}
+    options or= {}
     if str.length < 3 or not starts str, '"'
       @token 'STRING', str
     else

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 = or ''
+    idt or= ''
     children = (child.toString idt + TAB for child in @collectChildren()).join('')
     '\n' + idt + (override or @class) + children
 
@@ -187,7 +187,7 @@ exports.Expressions = class Expressions extends BaseNode
 
   # An **Expressions** is the only node that can serve as the root.
   compile: (o) ->
-    o = or {}
+    o or= {}
     if o.scope then super(o) else @compileRoot(o)
 
   compileNode: (o) ->
@@ -290,7 +290,7 @@ exports.ValueNode = class ValueNode extends BaseNode
 
   # A **ValueNode** has a base and a list of property accesses.
   constructor: (@base, @properties) ->
-    @properties = or []
+    @properties or= []
 
   # Add a property access to the list.
   push: (prop) ->
@@ -345,7 +345,7 @@ 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 = or this
+    o.chainRoot or= this
     baseline    = @base.compile o
     baseline    = "(#baseline)" if @hasProperties() and (@base instanceof ObjectNode or @isNumber())
     complete    = @last = baseline
@@ -397,7 +397,7 @@ exports.CallNode = class CallNode extends BaseNode
     @isNew    = false
     @isSuper  = variable is 'super'
     @variable = if @isSuper then null else variable
-    @args     = or []
+    @args     or= []
     @compileSplatArguments = (o) ->
       SplatNode.compileSplattedArray.call(this, @args, o)
 
@@ -489,7 +489,7 @@ exports.AccessorNode = class AccessorNode extends BaseNode
 
   compileNode: (o) ->
     name = @name.compile o
-    o.chainRoot.wrapped = or @soakNode
+    o.chainRoot.wrapped or= @soakNode
     namePart = if name.match(IS_STRING) then "[#name]" else ".#name"
     @prototype + namePart
 
@@ -504,7 +504,7 @@ exports.IndexNode = class IndexNode extends BaseNode
   constructor: (@index) ->
 
   compileNode: (o) ->
-    o.chainRoot.wrapped = or @soakNode
+    o.chainRoot.wrapped or= @soakNode
     idx = @index.compile o
     prefix = if @proto then '.prototype' else ''
     "#prefix[#idx]"
@@ -554,7 +554,7 @@ exports.RangeNode = class RangeNode extends BaseNode
     [from, to] = [parseInt(@fromNum, 10), parseInt(@toNum, 10)]
     idx        = del o, 'index'
     step       = del o, 'step'
-    step       = and "#idx += #{step.compile(o)}"
+    step       and= "#idx += #{step.compile(o)}"
     if from <= to
       "#idx = #from; #idx <#@equals #to; #{step or "#idx++"}"
     else
@@ -633,7 +633,7 @@ exports.ArrayNode = class ArrayNode extends BaseNode
   children: ['objects']
 
   constructor: (@objects) ->
-    @objects = or []
+    @objects or= []
     @compileSplatLiteral = (o) ->
       SplatNode.compileSplattedArray.call(this, @objects, o)
 
@@ -668,7 +668,7 @@ exports.ClassNode = class ClassNode extends BaseNode
   # Initialize a **ClassNode** with its name, an optional superclass, and a
   # list of prototype property assignments.
   constructor: (@variable, @parent, @properties) ->
-    @properties = or []
+    @properties or= []
     @returns    = false
 
   makeReturn: ->
@@ -707,8 +707,8 @@ exports.ClassNode = class ClassNode extends BaseNode
         continue
       if func instanceof CodeNode and func.bound
         func.bound = false
-        constScope = or new Scope(o.scope, constructor.body, constructor)
+        constScope or= new Scope(o.scope, constructor.body, constructor)
-        me = or constScope.freeVariable()
+        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); }"
@@ -838,8 +838,8 @@ exports.CodeNode = class CodeNode extends BaseNode
   children: ['params', 'body']
 
   constructor: (@params, @body, tag) ->
-    @params = or []
+    @params or= []
-    @body   = or new Expressions
+    @body   or= new Expressions
     @bound  = tag is 'boundfunc'
 
   # Compilation creates a new scope unless explicitly asked to share with the
@@ -893,7 +893,7 @@ exports.CodeNode = class CodeNode extends BaseNode
   traverseChildren: (crossScope, func) -> super(crossScope, func) if crossScope
 
   toString: (idt) ->
-    idt = or ''
+    idt or= ''
     children = (child.toString(idt + TAB) for child in @collectChildren()).join('')
     "\n#idt#children"
 
@@ -1251,7 +1251,7 @@ exports.ForNode = class ForNode extends BaseNode
   isStatement: -> yes
 
   constructor: (@body, source, @name, @index) ->
-    @index  = or null
+    @index  or= null
     @source = source.source
     @guard  = source.guard
     @step   = source.step
@@ -1340,7 +1340,7 @@ exports.IfNode = class IfNode extends BaseNode
   children: ['condition', 'switchSubject', 'body', 'elseBody', 'assigner']
 
   constructor: (@condition, @body, @tags) ->
-    @tags      = or {}
+    @tags      or= {}
     @condition = new OpNode('!', new ParentheticalNode(@condition)) if @tags.invert
     @elseBody = null
     @isChain  = false
@@ -1386,7 +1386,7 @@ 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 = or !!(@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(' || ')
@@ -1396,8 +1396,8 @@ exports.IfNode = class IfNode extends BaseNode
 
   makeReturn: ->
     if @isStatement()
-      @body     = and @ensureExpressions(@body.makeReturn())
+      @body     and= @ensureExpressions(@body.makeReturn())
-      @elseBody = and @ensureExpressions(@elseBody.makeReturn())
+      @elseBody and= @ensureExpressions(@elseBody.makeReturn())
       this
     else
       new ReturnNode this

src/rewriter.coffee

@@ -239,7 +239,7 @@ exports.Rewriter = class Rewriter
     @scanTokens (prev, token, post, i) =>
       for pair in pairs
         [open, close] = pair
-        levels[open] = or 0
+        levels[open] or= 0
         if token[0] is open
           openLine[open] = token[2] if levels[open] == 0
           levels[open] += 1

test/test_operations.coffee

@@ -68,14 +68,14 @@ ok x*+y is -50
 
 # Half-operators.
 one = two = null
-one = or 1
+one or= 1
-two = or  2
+two or=  2
 
 ok one is 1
 ok two is 2
 
-one = and 'one'
+one and= 'one'
-two = and  'two'
+two and=  'two'
 
 ok one is 'one'
 ok two is 'two'