basic class syntax

moonscript/compile/line.lua

@@ -6,7 +6,12 @@ require("moonscript.compile.format")
 local reversed = util.reversed
 local ntype = data.ntype
 local concat, insert = table.concat, table.insert
+local constructor_name = "new"
 line_compile = {
+  raw = function(self, node)
+    local _, text = unpack(node)
+    return self:add_line(text)
+  end,
   assign = function(self, node)
     local _, names, values = unpack(node)
     local undeclared = self:declare(names)
@@ -204,7 +209,7 @@ line_compile = {
     return nil
   end,
   ["class"] = function(self, node)
-    local _, name, table = unpack(node)
+    local _, name, tbl = unpack(node)
     local mt_name = "_" .. name .. "_mt"
     self:add_line("local", concat(self:declare({ name, mt_name }), ", "))
     local constructor = nil
@@ -213,7 +218,7 @@ line_compile = {
     local overloaded_index = value
     local find_special
     find_special = function(name, value)
-      if name == "constructor" then
+      if name == constructor_name then
         constructor = value
       elseif name:match("^__%a") then
         insert(meta_methods, { name, value })
@@ -224,7 +229,7 @@ line_compile = {
         return insert(final_properties, { name, value })
       end
     end
-    local _item_0 = table[2]
+    local _item_0 = tbl[2]
     for _index_0=1,#_item_0 do
       local entry = _item_0[_index_0]
       find_special(unpack(entry))
@@ -232,9 +237,6 @@ line_compile = {
     if not overloaded_index then
       insert(meta_methods, { "__index", { "table", final_properties } })
     end
-    print(util.dump(constructor))
-    print(util.dump(meta_methods))
-    print(util.dump(final_properties))
     self:stm({ "assign", { mt_name }, { { "table", meta_methods } } })
     if not constructor then
       constructor = {
@@ -262,7 +264,22 @@ line_compile = {
       end
       return _moon_0
     end)()
-    print(util.dump(constructor))
+    constructor[3] = "slim"
+    local body = constructor[4]
+    local dests = (function()
+      local _moon_0 = {}
+      local _item_0 = self_args
+      for _index_0=1,#_item_0 do
+        local name = _item_0[_index_0]
+        table.insert(_moon_0, { "self", name })
+      end
+      return _moon_0
+    end)()
+    if #self_args > 0 then
+      insert(body, 1, { "assign", dests, self_args })
+    end
+    insert(body, 1, { "raw", ("local self = setmetatable({}, %s)"):format(mt_name) })
+    insert(body, { "return", "self" })
     return self:stm({ "assign", { name }, { constructor } })
   end,
   comprehension = function(self, node, action)

moonscript/compile/line.moon

@@ -12,7 +12,12 @@ import concat, insert from table
 
 export line_compile
 
+constructor_name = "new"
+
 line_compile =
+  raw: (node) =>
+    _, text = unpack node
+    @add_line text
   assign: (node) =>
     _, names, values = unpack node
 
@@ -156,7 +161,7 @@ line_compile =
     nil
 
   ["class"]: (node) =>
-    _, name, table = unpack node
+    _, name, tbl = unpack node
     mt_name = "_"..name.."_mt"
     @add_line "local", concat @declare({ name, mt_name }), ", "
 
@@ -167,7 +172,7 @@ line_compile =
     overloaded_index = value
 
     find_special = (name, value) ->
-      if name == "constructor"
+      if name == constructor_name
         constructor = value
       elseif name:match("^__%a")
         insert meta_methods, {name, value}
@@ -175,15 +180,11 @@ line_compile =
       else
         insert final_properties, {name, value}
 
-    find_special unpack entry for entry in *table[2]
+    find_special unpack entry for entry in *tbl[2]
 
     if not overloaded_index
       insert meta_methods, {"__index", {"table", final_properties}}
 
-    print util.dump constructor
-    print util.dump meta_methods
-    print util.dump final_properties
-
     @stm {"assign", {mt_name}, {{"table", meta_methods}}}
 
     -- synthesize constructor
@@ -199,8 +200,14 @@ line_compile =
       arg
 
     constructor[2] = [get_initializers arg for arg in *constructor[2]]
+    constructor[3] = "slim"
+    body = constructor[4]
+
+    dests = [{"self", name} for name in *self_args]
+    insert body, 1, {"assign", dests, self_args} if #self_args > 0
+    insert body, 1, {"raw", ("local self = setmetatable({}, %s)"):format(mt_name)}
+    insert body, {"return", "self"}
 
-    print util.dump constructor
     @stm {"assign", {name}, {constructor}}
 
   comprehension: (node, action) =>

moonscript/parse.lua

@@ -227,7 +227,7 @@ local build_grammar = wrap(function()
 		Block = Ct(Line * (Break^1 * Line)^0),
 		Line = Cmt(Indent, check_indent) * Statement + _Space * Comment,
 
-		Statement = (Import + While + For + Export + BreakLoop + Ct(ExpList) / flatten_or_mark"explist" * Space) * (
+		Statement = (Import + While + For + ClassDecl + Export + BreakLoop + Ct(ExpList) / flatten_or_mark"explist" * Space) * (
 				-- statement decorators
 				key"if" * Exp * (key"else" * Exp)^-1 * Space / mark"if" +
 				CompInner / mark"comprehension"

tests/inputs/class.moon

@@ -0,0 +1,14 @@
+
+class Hello
+  new: (@test, @world) =>
+    print "creating object.."
+  hello: =>
+    print @test, @world
+  __tostring: => "hello world"
+
+x = Hello 1,2
+x:hello()
+
+print x
+
+

tests/outputs/class.lua

@@ -0,0 +1,11 @@
+local Hello, _Hello_mt
+_Hello_mt = { __tostring = function(self) return "hello world" end, __index = { hello = function(self) return print(self.test, self.world) end } }
+Hello = function(test, world)
+  local self = setmetatable({}, _Hello_mt)
+  self.test, self.world = test, world
+  print("creating object..")
+  return self
+end
+local x = Hello(1, 2)
+x:hello()
+print(x)