assignable name list in comprehension/decorator for in loop, fixes #236

Author: leafo

moonscript/parse.lua

@@ -142,7 +142,7 @@ local build_grammar = wrap_env(debug_grammar, function(root)
     Comprehension = sym("[") * Exp * CompInner * sym("]") / mark("comprehension"),
     TblComprehension = sym("{") * Ct(Exp * (sym(",") * Exp) ^ -1) * CompInner * sym("}") / mark("tblcomprehension"),
     CompInner = Ct((CompForEach + CompFor) * CompClause ^ 0),
-    CompForEach = key("for") * Ct(NameList) * key("in") * (sym("*") * Exp / mark("unpack") + Exp) / mark("foreach"),
+    CompForEach = key("for") * Ct(AssignableNameList) * key("in") * (sym("*") * Exp / mark("unpack") + Exp) / mark("foreach"),
     CompFor = key("for" * Name * sym("=") * Ct(Exp * sym(",") * Exp * (sym(",") * Exp) ^ -1) / mark("for")),
     CompClause = CompFor + CompForEach + key("when") * Exp / mark("when"),
     Assign = sym("=") * (Ct(With + If + Switch) + Ct(TableBlock + ExpListLow)) / mark("assign"),

moonscript/parse.moon

@@ -171,7 +171,7 @@ build_grammar = wrap_env debug_grammar, (root) ->
     TblComprehension: sym"{" * Ct(Exp * (sym"," * Exp)^-1) * CompInner * sym"}" / mark"tblcomprehension"
 
     CompInner: Ct((CompForEach + CompFor) * CompClause^0)
-    CompForEach: key"for" * Ct(NameList) * key"in" * (sym"*" * Exp / mark"unpack" + Exp) / mark"foreach"
+    CompForEach: key"for" * Ct(AssignableNameList) * key"in" * (sym"*" * Exp / mark"unpack" + Exp) / mark"foreach"
     CompFor: key "for" * Name * sym"=" * Ct(Exp * sym"," * Exp * (sym"," * Exp)^-1) / mark"for"
     CompClause: CompFor + CompForEach + key"when" * Exp / mark"when"
 

spec/inputs/comprehension.moon

@@ -30,4 +30,17 @@ dd = [y for i=1,10 when cool for thing in y when x > 3 when c + 3]
 
 {"hello", "world" for i=1,10}
 
+--
+
+j = [a for {a,b,c} in things]
+k = [a for {a,b,c} in *things]
+i = [hello for {:hello, :world} in *things]
+
+hj = {a,c for {a,b,c} in things}
+hk = {a,c for {a,b,c} in *things}
+hi = {hello,world for {:hello, :world} in *things}
+
+ok(a,b,c) for {a,b,c} in things
+
+
 nil

spec/outputs/comprehension.lua

@@ -168,4 +168,83 @@ do
   end
   _ = _tbl_0
 end
+local j
+do
+  local _accum_0 = { }
+  local _len_0 = 1
+  for _des_0 in things do
+    local a, b, c
+    a, b, c = _des_0[1], _des_0[2], _des_0[3]
+    _accum_0[_len_0] = a
+    _len_0 = _len_0 + 1
+  end
+  j = _accum_0
+end
+local k
+do
+  local _accum_0 = { }
+  local _len_0 = 1
+  local _list_0 = things
+  for _index_0 = 1, #_list_0 do
+    local _des_0 = _list_0[_index_0]
+    local a, b, c
+    a, b, c = _des_0[1], _des_0[2], _des_0[3]
+    _accum_0[_len_0] = a
+    _len_0 = _len_0 + 1
+  end
+  k = _accum_0
+end
+local i
+do
+  local _accum_0 = { }
+  local _len_0 = 1
+  local _list_0 = things
+  for _index_0 = 1, #_list_0 do
+    local _des_0 = _list_0[_index_0]
+    local hello, world
+    hello, world = _des_0.hello, _des_0.world
+    _accum_0[_len_0] = hello
+    _len_0 = _len_0 + 1
+  end
+  i = _accum_0
+end
+local hj
+do
+  local _tbl_0 = { }
+  for _des_0 in things do
+    local a, b, c
+    a, b, c = _des_0[1], _des_0[2], _des_0[3]
+    _tbl_0[a] = c
+  end
+  hj = _tbl_0
+end
+local hk
+do
+  local _tbl_0 = { }
+  local _list_0 = things
+  for _index_0 = 1, #_list_0 do
+    local _des_0 = _list_0[_index_0]
+    local a, b, c
+    a, b, c = _des_0[1], _des_0[2], _des_0[3]
+    _tbl_0[a] = c
+  end
+  hk = _tbl_0
+end
+local hi
+do
+  local _tbl_0 = { }
+  local _list_0 = things
+  for _index_0 = 1, #_list_0 do
+    local _des_0 = _list_0[_index_0]
+    local hello, world
+    hello, world = _des_0.hello, _des_0.world
+    _tbl_0[hello] = world
+  end
+  hi = _tbl_0
+end
+for _des_0 in things do
+  local a, b, c
+  a, b, c = _des_0[1], _des_0[2], _des_0[3]
+  ok(a, b, c)
+end
 return nil