Added support for compile actions returning trees, and compiling blocks

into values.

core/metaprogramming.nom

@@ -197,16 +197,14 @@ compile [parse %actions as %body] to (..)
         end
         local \%new_body = LuaCode(\%body.source,
             "local mangle = mangler()",
-            "\\nlocal tree = ", make_tree(\%body),
+            "\\nreturn ", make_tree(\%body))
-            "\\nlocal lua = nomsu:compile(tree)",
-            "\\nreturn lua")
         local ret = \(compile as (compile %actions to %new_body))
         return ret"
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 # TODO: add check for .is_value
-compile [%tree as lua expr] to (Lua value "nomsu:compile(\(=lua "nomsu:compile(\%tree)"))")
+compile [%tree as lua expr] to (Lua value "nomsu:compile(\(=lua "nomsu:compile(\%tree, nil, true)"), nil, true)")
 
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

core/operators.nom

@@ -27,16 +27,9 @@ test:
 
 # Variable assignment operator
 compile [%var = %value] to:
-    lua> "local \%var_lua = \(%var as lua)"
+    lua> "local \%var_lua = \(%var as lua expr)"
     assume %var_lua.is_value or barf "Invalid target for assignment: \%var"
-    lua> "\
+    lua> "local \%value_lua = \(%value as lua expr)"
-        ..\%value = \%value:map(function(t)
-            if Action:is_instance(t) and t.stub == "?" then
-                return \%var
-            end
-        end)
-        local \%value_lua = \(%value as lua)"
-    
     assume %value_lua.is_value or barf "Invalid value for assignment: \%value"
     lua> "\
         ..local lua = LuaCode(tree.source, \%var_lua, ' = ', \%value_lua, ';')

nomsu_compiler.lua

@@ -667,7 +667,10 @@ do
     end
     return run_lua_fn()
   end
-  NomsuCompiler.compile = function(self, tree, compile_actions)
+  NomsuCompiler.compile = function(self, tree, compile_actions, force_value)
+    if force_value == nil then
+      force_value = false
+    end
     compile_actions = compile_actions or self.environment.COMPILE_ACTIONS
     if tree.version then
       do
@@ -736,7 +739,7 @@ do
             _continue_0 = true
             break
           end
-          local arg_lua = self:compile(tok, compile_actions)
+          local arg_lua = self:compile(tok, compile_actions, true)
           if not (arg_lua.is_value) then
             if tok.type == "Block" then
               self:compile_error(tok, "Can't compile action (" .. tostring(stub) .. ") with a Block as an argument.", "Maybe there should be a compile-time action with that name that isn't being found?")
@@ -781,6 +784,7 @@ do
       lua:append("}")
       return lua
     elseif "Block" == _exp_0 then
+      if not force_value then
         local lua = LuaCode(tree.source)
         lua:concat_append((function()
           local _accum_0 = { }
@@ -793,6 +797,43 @@ do
           return _accum_0
         end)(), "\n")
         return lua
+      else
+        local lua = LuaCode.Value(tree.source)
+        local values
+        do
+          local _accum_0 = { }
+          local _len_0 = 1
+          for _index_0 = 1, #tree do
+            local line = tree[_index_0]
+            _accum_0[_len_0] = self:compile(line)
+            _len_0 = _len_0 + 1
+          end
+          values = _accum_0
+        end
+        local all_values = true
+        for _index_0 = 1, #values do
+          local v = values[_index_0]
+          all_values = all_values and v.is_value
+        end
+        if all_values then
+          if #values == 1 then
+            return values[1]
+          end
+          lua:append("(")
+          lua:concat_append(values, " and nil or ")
+          lua:append(")")
+        else
+          lua:append("((function()")
+          for i, v in ipairs(values) do
+            if v.is_value then
+              v = v:as_statements(i == #values and 'return ' or '')
+            end
+            lua:append("\n    ", v)
+          end
+          lua:append("\nend)())")
+        end
+        return lua
+      end
     elseif "Text" == _exp_0 then
       local lua = LuaCode.Value(tree.source)
       local string_buffer = ""

nomsu_compiler.moon

@@ -389,7 +389,7 @@ with NomsuCompiler
 
         return run_lua_fn!
 
-    .compile = (tree, compile_actions)=>
+    .compile = (tree, compile_actions, force_value=false)=>
         compile_actions or= @environment.COMPILE_ACTIONS
         if tree.version
             if get_version = @[("Nomsu version")\as_lua_id!]
@@ -430,7 +430,7 @@ with NomsuCompiler
                 args = {}
                 for i, tok in ipairs tree
                     if type(tok) == "string" then continue
-                    arg_lua = @compile(tok, compile_actions)
+                    arg_lua = @compile(tok, compile_actions, true)
                     unless arg_lua.is_value
                         if tok.type == "Block"
                             @compile_error tok,
@@ -469,9 +469,28 @@ with NomsuCompiler
                 return lua
             
             when "Block"
+                if not force_value
                     lua = LuaCode(tree.source)
                     lua\concat_append([@compile(line, compile_actions)\as_statements! for line in *tree], "\n")
                     return lua
+                else
+                    lua = LuaCode.Value(tree.source)
+                    values = [@compile(line) for line in *tree]
+                    all_values = true
+                    for v in *values do all_values and= v.is_value
+                    if all_values
+                        return values[1] if #values == 1
+                        lua\append "("
+                        lua\concat_append(values, " and nil or ")
+                        lua\append ")"
+                    else
+                        lua\append("((function()")
+                        for i, v in ipairs(values)
+                            if v.is_value
+                                v = v\as_statements(i == #values and 'return ' or '')
+                            lua\append "\n    ", v
+                        lua\append("\nend)())")
+                    return lua
 
             when "Text"
                 lua = LuaCode.Value(tree.source)