Merge branch 'bjorn/maps'

* bjorn/maps:
  Document the new {badmap,Term} and {badkey,Key} exceptions
  Raise more descriptive error messages for failed map operations
  erl_term.h: Add is_not_map() macro
  Tigthen code for the i_get_map_elements/3 instruction
  Pre-compute hash values for the general get_map_elements instruction
  Teach the loader to pre-compute the hash value for single-key lookups
  Optimize use of i_get_map_element/4
  beam_emu: Slightly optimize update_map_{assoc,exact}
  v3_codegen: Don't sort map keys in map creation/update
  beam_validator: No longer require strict literal term order
  Sort maps keys in the loader
  De-optimize the has_map_fields instructions
  erts/map_SUITE.erl: Add a test case that tests has_map_fields
  Fully evaluate is_map/1 for literals at load-time
  map_SUITE: Add tests of is_map/1 with literal maps
  Run a clone of map_SUITE without optimizations
  Remove the fail label operand of the new_map instruction
  Correct transformation of put_map_assoc to new_map
  Remove support for put_map_exact without a source map

1 files changed, 8 insertions, 12 deletions

diff --git a/lib/stdlib/src/erl_eval.erl b/lib/stdlib/src/erl_eval.erl
index 371573dc23..e86e10b170 100644
--- a/lib/stdlib/src/erl_eval.erl
+++ b/lib/stdlib/src/erl_eval.erl
@@ -246,18 +246,14 @@ expr({record,_,_,Name,_}, _Bs, _Lf, _Ef, _RBs) ->
 %% map
 expr({map,_,Binding,Es}, Bs0, Lf, Ef, RBs) ->
     {value, Map0, Bs1} = expr(Binding, Bs0, Lf, Ef, none),
-    case Map0 of
-        #{} ->
-            {Vs,Bs2} = eval_map_fields(Es, Bs0, Lf, Ef),
-            Map1 = lists:foldl(fun ({map_assoc,K,V}, Mi) ->
-                                       maps:put(K, V, Mi);
-                                   ({map_exact,K,V}, Mi) ->
-                                       maps:update(K, V, Mi)
-                               end, Map0, Vs),
-            ret_expr(Map1, merge_bindings(Bs2, Bs1), RBs);
-        _ ->
-            erlang:raise(error, {badarg,Map0}, stacktrace())
-    end;
+    {Vs,Bs2} = eval_map_fields(Es, Bs0, Lf, Ef),
+    _ = maps:put(k, v, Map0),			%Validate map.
+    Map1 = lists:foldl(fun ({map_assoc,K,V}, Mi) ->
+			       maps:put(K, V, Mi);
+			   ({map_exact,K,V}, Mi) ->
+			       maps:update(K, V, Mi)
+		       end, Map0, Vs),
+    ret_expr(Map1, merge_bindings(Bs2, Bs1), RBs);
 expr({map,_,Es}, Bs0, Lf, Ef, RBs) ->
     {Vs,Bs} = eval_map_fields(Es, Bs0, Lf, Ef),
     ret_expr(lists:foldl(fun