File 2251-Remove-undocumented-value-Value-Ann-in-erl... of Package erlang

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File 2251-Remove-undocumented-value-Value-Ann-in-erl_eval.patch of Package erlang (Revision 371fc947ce89baa340e0441f200e4667)

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From 223913f95592cb72f090b892107b8e5e7e4a8f97 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Valim?= <jose.valim@dashbit.co>
Date: Tue, 7 Dec 2021 12:34:30 +0100
Subject: [PATCH] Remove undocumented {value, Value, Ann} in erl_eval

The shell relies on an implicit contract
with erl_eval where value triplet is allowed.
Unfortunately, to support this, evaluating
anonymous functions would require a look-ahead
traversal to hide any value triplet from
erl_lint and this affected performance negatively.

This patch removes this undocumented contract
and removes the lookahead. To address this,
we took different approaches:

1. v(N) was expanded to a value before evaluated.
     Now, we process and validate the arguments,
     but communicate with the shell process to get
     the value, similar to how history() works

2. References, Ports, and PIDs were converted to
     variables and then replaced to values. Now,
     we expand `#PID<0.13.0>` into an expression
     such as `erlang:list_to_pid("#PID<0.13.0>").`

3. Finally, the prompt evaluation would use values,
     but it only had to pass `[{history,integer()}]`,
     which can be manually converted to AST

With this change, evaluating anonymous functions in
a loop gets considerably faster, up to 10% in a
macro benchmark.
---
 lib/debugger/src/dbg_icmd.erl |  32 ++----
 lib/stdlib/src/erl_eval.erl   | 200 ++++++++++++++--------------------
 lib/stdlib/src/qlc.erl        |  21 ++--
 lib/stdlib/src/shell.erl      |  23 ++--
 lib/stdlib/test/qlc_SUITE.erl |  40 +++----
 5 files changed, 129 insertions(+), 187 deletions(-)

diff --git a/lib/debugger/src/dbg_icmd.erl b/lib/debugger/src/dbg_icmd.erl
index 0eb258567f..8d10fdb2c7 100644
--- a/lib/debugger/src/dbg_icmd.erl
+++ b/lib/debugger/src/dbg_icmd.erl
@@ -382,19 +382,14 @@ eval_restricted({From,_Mod,Cmd,SP}, Bs) ->
     case catch parse_cmd(Cmd, 1) of
 	{'EXIT', _Reason} ->
 	    From ! {self(), {eval_rsp, 'Parse error'}};
-	{[{var,_,Var}], XBs} ->
+	[{var,_,Var}] ->
 	    Bs2 = bindings(Bs, SP),
 	    Res = case get_binding(Var, Bs2) of
 		      {value, Value} -> Value;
-		      unbound ->
-                          case get_binding(Var, XBs) of
-                              {value, _} ->
-                                  'Only possible to inspect variables';
-                              unbound -> unbound
-                          end
+		      unbound -> unbound
 		  end,
 	    From ! {self(), {eval_rsp, Res}};
-	{_Forms, _XBs} ->
+	_Forms ->
 	    Rsp = 'Only possible to inspect variables',
 	    From ! {self(), {eval_rsp, Rsp}}
     end.
@@ -409,18 +404,17 @@ eval_nonrestricted({From, _Mod, Cmd, _SP}, Bs,
 	{'EXIT', _Reason} ->
 	    From ! {self(), {eval_rsp, 'Parse error'}},
 	    Bs;
-	{Forms, XBs} ->
+	Forms ->
 	    mark_running(Line, Le),
-            Bs1 = merge_bindings(Bs, XBs),
-	    {Res, Bs2} =
+	    {Res, Bs1} =
 		lists:foldl(fun(Expr, {_Res, Bs0}) ->
 				    eval_nonrestricted_1(Expr,Bs0,Ieval)
 			    end,
-			    {null, Bs1},
+			    {null, Bs},
 			    Forms),
 	    mark_break(M, Line, Le),
 	    From ! {self(), {eval_rsp, Res}},
-	    remove_binding_structs(Bs2, XBs)
+	    Bs1
     end.
 
 eval_nonrestricted_1({match,_,{var,_,Var},Expr}, Bs, Ieval) ->
@@ -445,14 +439,6 @@ eval_expr(Expr, Bs, Ieval) ->
         dbg_ieval:eval_expr(Expr, Bs, Ieval#ieval{top=false}),
     {Res,Bs2}.
 
-%% XBs have unique keys.
-merge_bindings(Bs1, XBs) ->
-    Bs1 ++ erl_eval:bindings(XBs).
-
-remove_binding_structs(Bs1, XBs) ->
-    lists:foldl(fun({N, _V}, Bs) -> lists:keydelete(N, 1, Bs)
-                end, Bs1, erl_eval:bindings(XBs)).
-
 mark_running(LineNo, Le) ->
     put(next_break, running),
     put(user_eval, [{LineNo, Le} | get(user_eval)]),
@@ -467,8 +453,8 @@ mark_break(Cm, LineNo, Le) ->
 
 parse_cmd(Cmd, LineNo) ->
     {ok,Tokens,_} = erl_scan:string(Cmd, LineNo, [text]),
-    {ok,Forms,Bs} = erl_eval:extended_parse_exprs(Tokens),
-    {Forms, Bs}.
+    {ok,Forms} = erl_eval:extended_parse_exprs(Tokens),
+    Forms.
 
 %%====================================================================
 %% Library functions for attached process handling
diff --git a/lib/stdlib/src/erl_eval.erl b/lib/stdlib/src/erl_eval.erl
index dcd5e61fbd..bcb271b1b5 100644
--- a/lib/stdlib/src/erl_eval.erl
+++ b/lib/stdlib/src/erl_eval.erl
@@ -24,8 +24,7 @@
 -export([exprs/2,exprs/3,exprs/4,expr/2,expr/3,expr/4,expr/5,
          expr_list/2,expr_list/3,expr_list/4]).
 -export([new_bindings/0,bindings/1,binding/2,add_binding/3,del_binding/2]).
--export([extended_parse_exprs/1, extended_parse_term/1,
-         subst_values_for_vars/2]).
+-export([extended_parse_exprs/1, extended_parse_term/1]).
 -export([is_constant_expr/1, partial_eval/1, eval_str/1]).
 
 %% Is used by standalone Erlang (escript).
@@ -284,10 +283,7 @@ expr({'fun',_Anno,{function,Name,Arity}}, _Bs0, _Lf, _Ef, _RBs) -> % R8
     %% Don't know what to do...
     erlang:raise(error, undef, [{?MODULE,Name,Arity}|?STACKTRACE]);
 expr({'fun',Anno,{clauses,Cs}} = Ex, Bs, Lf, Ef, RBs) ->
-    %% Save only used variables in the function environment.
-    %% {value,L,V} are hidden while lint finds used variables.
-    {Ex1, _} = hide_calls(Ex, 0),
-    {ok,Used} = erl_lint:used_vars([Ex1], bindings(Bs)),
+    {ok,Used} = erl_lint:used_vars([Ex], bindings(Bs)),
     En = filter_bindings(fun(K,_V) -> member(K,Used) end, Bs),
     Info = {En,Lf,Ef,Cs},
     %% This is a really ugly hack!
@@ -332,10 +328,7 @@ expr({'fun',Anno,{clauses,Cs}} = Ex, Bs, Lf, Ef, RBs) ->
     end,
     ret_expr(F, Bs, RBs);
 expr({named_fun,Anno,Name,Cs} = Ex, Bs, Lf, Ef, RBs) ->
-    %% Save only used variables in the function environment.
-    %% {value,L,V} are hidden while lint finds used variables.
-    {Ex1, _} = hide_calls(Ex, 0),
-    {ok,Used} = erl_lint:used_vars([Ex1], bindings(Bs)),
+    {ok,Used} = erl_lint:used_vars([Ex], bindings(Bs)),
     En = filter_bindings(fun(K,_V) -> member(K,Used) end, Bs),
     Info = {En,Lf,Ef,Cs,Name},
     %% This is a really ugly hack!
@@ -508,10 +501,7 @@ hide_calls(LC, MaxLine) ->
     {NLC, _, D} = hide(LC, LineId0, maps:new()),
     {NLC, D}.
 
-%% v/1 and local calls are hidden.
-hide({value,L,V}, Id, D) ->
-    A = erl_anno:new(Id),
-    {{atom,A,ok}, Id+1, maps:put(Id, {value,L,V}, D)};
+%% Local calls are hidden from qlc so they are not expanded.
 hide({call,A,{atom,_,N}=Atom,Args}, Id0, D0) ->
     {NArgs, Id, D} = hide(Args, Id0, D0),
     C = case erl_internal:bif(N, length(Args)) of
@@ -532,14 +522,6 @@ hide([E0 | Es0], Id0, D0) ->
 hide(E, Id, D) -> 
     {E, Id, D}.
 
-unhide_calls({atom,A,ok}=E, MaxLine, D) ->
-    L = erl_anno:line(A),
-    if
-        L > MaxLine ->
-            map_get(L, D);
-        true ->
-            E
-    end;
 unhide_calls({call,Anno,{remote,A,{atom,A,m},{atom,A,f}}=F,Args},
              MaxLine, D) ->
     Line = erl_anno:line(Anno),
@@ -1323,28 +1305,6 @@ to_terms(Abstrs) ->
 to_term(Abstr) ->
     erl_parse:anno_to_term(Abstr).
 
-%% Substitute {value, A, Item} for {var, A, Var}, preserving A.
-%% {value, A, Item} is a shell/erl_eval convention, and for example
-%% the linter cannot handle it.
-
--spec subst_values_for_vars(ExprList, Bindings) -> [term()] when
-      ExprList :: [erl_parse:abstract_expr()],
-      Bindings :: binding_struct().
-
-subst_values_for_vars({var, A, V}=Var, Bs) ->
-    case erl_eval:binding(V, Bs) of
-        {value, Value} ->
-            {value, A, Value};
-        unbound ->
-            Var
-    end;
-subst_values_for_vars(L, Bs) when is_list(L) ->
-    [subst_values_for_vars(E, Bs) || E <- L];
-subst_values_for_vars(T, Bs) when is_tuple(T) ->
-    list_to_tuple(subst_values_for_vars(tuple_to_list(T), Bs));
-subst_values_for_vars(T, _Bs) ->
-    T.
-
 %% `Tokens' is assumed to have been scanned with the 'text' option.
 %% The annotations of the returned expressions are locations.
 %%
@@ -1353,18 +1313,17 @@ subst_values_for_vars(T, _Bs) ->
 %% the items themselves are stored in the returned bindings.
 
 -spec extended_parse_exprs(Tokens) ->
-                {'ok', ExprList, Bindings} | {'error', ErrorInfo} when
+                {'ok', ExprList} | {'error', ErrorInfo} when
       Tokens :: [erl_scan:token()],
       ExprList :: [erl_parse:abstract_expr()],
-      Bindings :: erl_eval:binding_struct(),
       ErrorInfo :: erl_parse:error_info().
 
 extended_parse_exprs(Tokens) ->
     Ts = tokens_fixup(Tokens),
     case erl_parse:parse_exprs(Ts) of
         {ok, Exprs0} ->
-            {Exprs, Bs} = expr_fixup(Exprs0),
-            {ok, reset_expr_anno(Exprs), Bs};
+            Exprs = expr_fixup(Exprs0),
+            {ok, reset_expr_anno(Exprs)};
         _ErrorInfo ->
             erl_parse:parse_exprs(reset_token_anno(Ts))
     end.
@@ -1382,7 +1341,7 @@ tokens_fixup([T|Ts]=Ts0) ->
 token_fixup(Ts) ->
     {AnnoL, NewTs, FixupTag} = unscannable(Ts),
     String = lists:append([erl_anno:text(A) || A <- AnnoL]),
-    _ = (fixup_fun(FixupTag))(String),
+    _ = validate_tag(FixupTag, String),
     NewAnno = erl_anno:set_text(fixup_text(FixupTag), hd(AnnoL)),
     {{string, NewAnno, String}, NewTs}.
 
@@ -1403,37 +1362,26 @@ unscannable([{'#', A1}, {var, A2, 'Ref'}, {'<', A3}, {float, A4, _},
              {'.', A5}, {float, A6, _}, {'>', A7}|Ts]) ->
     {[A1, A2, A3, A4, A5, A6, A7], Ts, reference}.
 
-expr_fixup(Expr0) ->
-    {Expr, Bs, _} = expr_fixup(Expr0, erl_eval:new_bindings(), 1),
-    {Expr, Bs}.
-
-expr_fixup({string,A,S}=T, Bs0, I) ->
-    try string_fixup(A, S) of
-        Value ->
-            Var = new_var(I),
-            Bs = erl_eval:add_binding(Var, Value, Bs0),
-            {{var, A, Var}, Bs, I+1}
+expr_fixup({string,A,S}=T) ->
+    try string_fixup(A, S, T) of
+        Expr -> Expr
     catch
-        _:_ ->
-            {T, Bs0, I}
+        _:_ -> T
     end;
-expr_fixup(Tuple, Bs0, I0) when is_tuple(Tuple) ->
-    {L, Bs, I} = expr_fixup(tuple_to_list(Tuple), Bs0, I0),
-    {list_to_tuple(L), Bs, I};
-expr_fixup([E0|Es0], Bs0, I0) ->
-    {E, Bs1, I1} = expr_fixup(E0, Bs0, I0),
-    {Es, Bs, I} = expr_fixup(Es0, Bs1, I1),
-    {[E|Es], Bs, I};
-expr_fixup(T, Bs, I) ->
-    {T, Bs, I}.
-
-string_fixup(A, S) ->
-    Text = erl_anno:text(A),
-    FixupTag = fixup_tag(Text, S),
-    (fixup_fun(FixupTag))(S).
-
-new_var(I) ->
-    list_to_atom(lists:concat(['__ExtendedParseExprs_', I, '__'])).
+expr_fixup(Tuple) when is_tuple(Tuple) ->
+    L = expr_fixup(tuple_to_list(Tuple)),
+    list_to_tuple(L);
+expr_fixup([E0|Es0]) ->
+    E = expr_fixup(E0),
+    Es = expr_fixup(Es0),
+    [E|Es];
+expr_fixup(T) ->
+    T.
+
+string_fixup(Ann, String, Token) ->
+    Text = erl_anno:text(Ann),
+    FixupTag = fixup_tag(Text, String),
+    fixup_ast(FixupTag, Ann, String, Token).
 
 reset_token_anno(Tokens) ->
     [setelement(2, T, (reset_anno())(element(2, T))) || T <- Tokens].
@@ -1444,18 +1392,15 @@ reset_expr_anno(Exprs) ->
 reset_anno() ->
     fun(A) -> erl_anno:new(erl_anno:location(A)) end.
 
-fixup_fun(function)  -> fun function/1;
-fixup_fun(pid)       -> fun erlang:list_to_pid/1;
-fixup_fun(port)      -> fun erlang:list_to_port/1;
-fixup_fun(reference) -> fun erlang:list_to_ref/1.
-
-function(S) ->
-    %% External function.
-    {ok, [_, _, _,
-          {atom, _, Module}, _,
-          {atom, _, Function}, _,
-          {integer, _, Arity}|_], _} = erl_scan:string(S),
-    erlang:make_fun(Module, Function, Arity).
+fixup_ast(pid, A, _S, T) ->
+    {call,A,{remote,A,{atom,A,erlang},{atom,A,list_to_pid}},[T]};
+fixup_ast(port, A, _S, T) ->
+    {call,A,{remote,A,{atom,A,erlang},{atom,A,list_to_port}},[T]};
+fixup_ast(reference, A, _S, T) ->
+    {call,A,{remote,A,{atom,A,erlang},{atom,A,list_to_ref}},[T]};
+fixup_ast(function, A, S, _T) ->
+    {Module, Function, Arity} = fixup_mfa(S),
+    {'fun',A,{function,{atom,A,Module},{atom,A,Function},{integer,A,Arity}}}.
 
 fixup_text(function)  -> "function";
 fixup_text(pid)       -> "pid";
@@ -1467,6 +1412,20 @@ fixup_tag("pid",       "<"++_) -> pid;
 fixup_tag("port",      "#"++_) -> port;
 fixup_tag("reference", "#"++_) -> reference.
 
+fixup_mfa(S) ->
+    {ok, [_, _, _,
+          {atom, _, Module}, _,
+          {atom, _, Function}, _,
+          {integer, _, Arity}|_], _} = erl_scan:string(S),
+    {Module, Function, Arity}.
+
+validate_tag(pid, String) -> erlang:list_to_pid(String);
+validate_tag(port, String) -> erlang:list_to_port(String);
+validate_tag(reference, String) -> erlang:list_to_ref(String);
+validate_tag(function, String) ->
+    {Module, Function, Arity} = fixup_mfa(String),
+    erlang:make_fun(Module, Function, Arity).
+
 %%% End of extended_parse_exprs.
 
 %% `Tokens' is assumed to have been scanned with the 'text' option.
@@ -1481,8 +1440,8 @@ fixup_tag("reference", "#"++_) -> reference.
 
 extended_parse_term(Tokens) ->
     case extended_parse_exprs(Tokens) of
-        {ok, [Expr], Bindings} ->
-            try normalise(Expr, Bindings) of
+        {ok, [Expr]} ->
+            try normalise(Expr) of
                 Term ->
                     {ok, Term}
             catch
@@ -1490,7 +1449,7 @@ extended_parse_term(Tokens) ->
                     Loc = erl_anno:location(element(2, Expr)),
                     {error,{Loc,?MODULE,"bad term"}}
             end;
-        {ok, [_,Expr|_], _Bindings} ->
+        {ok, [_,Expr|_]} ->
                 Loc = erl_anno:location(element(2, Expr)),
                 {error,{Loc,?MODULE,"bad term"}};
         {error, _} = Error ->
@@ -1498,46 +1457,47 @@ extended_parse_term(Tokens) ->
     end.
 
 %% From erl_parse.
-normalise({var, _, V}, Bs) ->
-    {value, Value} = erl_eval:binding(V, Bs),
-    Value;
-normalise({char,_,C}, _Bs) -> C;
-normalise({integer,_,I}, _Bs) -> I;
-normalise({float,_,F}, _Bs) -> F;
-normalise({atom,_,A}, _Bs) -> A;
-normalise({string,_,S}, _Bs) -> S;
-normalise({nil,_}, _Bs) -> [];
-normalise({bin,_,Fs}, Bs) ->
+normalise({char,_,C}) -> C;
+normalise({integer,_,I}) -> I;
+normalise({float,_,F}) -> F;
+normalise({atom,_,A}) -> A;
+normalise({string,_,S}) -> S;
+normalise({nil,_}) -> [];
+normalise({bin,_,Fs}) ->
     {value, B, _} =
 	eval_bits:expr_grp(Fs, [],
 			   fun(E, _) ->
-				   {value, normalise(E, Bs), []}
+				   {value, normalise(E), []}
 			   end, [], true),
     B;
-normalise({cons,_,Head,Tail}, Bs) ->
-    [normalise(Head, Bs)|normalise(Tail, Bs)];
-normalise({tuple,_,Args}, Bs) ->
-    list_to_tuple(normalise_list(Args, Bs));
-normalise({map,_,Pairs}, Bs) ->
+normalise({cons,_,Head,Tail}) ->
+    [normalise(Head)|normalise(Tail)];
+normalise({tuple,_,Args}) ->
+    list_to_tuple(normalise_list(Args));
+normalise({map,_,Pairs}) ->
     maps:from_list(lists:map(fun
 		%% only allow '=>'
 		({map_field_assoc,_,K,V}) ->
-                                     {normalise(K, Bs),normalise(V, Bs)}
+                                     {normalise(K),normalise(V)}
 	    end, Pairs));
 %% Special case for unary +/-.
-normalise({op,_,'+',{char,_,I}}, _Bs) -> I;
-normalise({op,_,'+',{integer,_,I}}, _Bs) -> I;
-normalise({op,_,'+',{float,_,F}}, _Bs) -> F;
-normalise({op,_,'-',{char,_,I}}, _Bs) -> -I;   %Weird, but compatible!
-normalise({op,_,'-',{integer,_,I}}, _Bs) -> -I;
-normalise({op,_,'-',{float,_,F}}, _Bs) -> -F;
-normalise({'fun',_,{function,{atom,_,M},{atom,_,F},{integer,_,A}}}, _Bs) ->
+normalise({op,_,'+',{char,_,I}}) -> I;
+normalise({op,_,'+',{integer,_,I}}) -> I;
+normalise({op,_,'+',{float,_,F}}) -> F;
+normalise({op,_,'-',{char,_,I}}) -> -I;   %Weird, but compatible!
+normalise({op,_,'-',{integer,_,I}}) -> -I;
+normalise({op,_,'-',{float,_,F}}) -> -F;
+%% Special case for #...<>
+normalise({call,_,{remote,_,{atom,_,erlang},{atom,_,Fun}},[{string,_,S}]}) when
+        Fun =:= list_to_ref; Fun =:= list_to_port; Fun =:= list_to_pid ->
+    erlang:Fun(S);
+normalise({'fun',_,{function,{atom,_,M},{atom,_,F},{integer,_,A}}}) ->
     %% Since "#Fun<M.F.A>" is recognized, "fun M:F/A" should be too.
     fun M:F/A.
 
-normalise_list([H|T], Bs) ->
-    [normalise(H, Bs)|normalise_list(T, Bs)];
-normalise_list([], _Bs) ->
+normalise_list([H|T]) ->
+    [normalise(H)|normalise_list(T)];
+normalise_list([]) ->
     [].
 
 %%----------------------------------------------------------------------------
diff --git a/lib/stdlib/src/qlc.erl b/lib/stdlib/src/qlc.erl
index d0e416805f..e9d9c01b7d 100644
--- a/lib/stdlib/src/qlc.erl
+++ b/lib/stdlib/src/qlc.erl
@@ -652,21 +652,20 @@ string_to_handle(Str, Options, Bindings) when is_list(Str) ->
                 {ok, Tokens, _} ->
                     ScanRes =
                         case erl_eval:extended_parse_exprs(Tokens) of
-                            {ok, [Expr0], SBs} ->
-                                {ok, Expr0, SBs};
-                            {ok, _ExprList, _SBs} ->
+                            {ok, [Expr0]} ->
+                                {ok, Expr0};
+                            {ok, _ExprList} ->
                                 erlang:error(badarg,
                                              [Str, Options, Bindings]);
                             E ->
                                 E
                         end,
                     case ScanRes of
-                        {ok, Expr, XBs} ->
-                            Bs1 = merge_binding_structs(Bindings, XBs),
-                            case qlc_pt:transform_expression(Expr, Bs1) of
+                        {ok, Expr} ->
+                            case qlc_pt:transform_expression(Expr, Bindings) of
                                 {ok, {call, _, _QlcQ,  Handle}} ->
                                     {value, QLC_lc, _} = 
-                                        erl_eval:exprs(Handle, Bs1),
+                                        erl_eval:exprs(Handle, Bindings),
                                     O = #qlc_opt{unique = Unique, 
                                                  cache = Cache,
                                                  max_lookup = MaxLookup, 
@@ -792,10 +791,6 @@ all_selections([{I,Cs} | ICs]) ->
 %%% Local functions
 %%%
 
-merge_binding_structs(Bs1, Bs2) ->
-    lists:foldl(fun({N, V}, Bs) -> erl_eval:add_binding(N, V, Bs)
-                end, Bs1, erl_eval:bindings(Bs2)).
-
 aux_name1(Name, N, AllNames) ->
     SN = name_suffix(Name, N),
     case gb_sets:is_member(SN, AllNames) of
@@ -1208,9 +1203,7 @@ abstract1({table, TableDesc}, _NElements, _Depth, _A) ->
         true ->
             {ok, Tokens, _} =
                 erl_scan:string(lists:flatten(TableDesc++"."), 1, [text]),
-            {ok, Es, Bs} =
-                erl_eval:extended_parse_exprs(Tokens),
-            [Expr] = erl_eval:subst_values_for_vars(Es, Bs),
+            {ok, [Expr]} = erl_eval:extended_parse_exprs(Tokens),
             special(Expr);
         false -> % abstract expression
             TableDesc
diff --git a/lib/stdlib/src/shell.erl b/lib/stdlib/src/shell.erl
index ac6c185860..2764de616e 100644
--- a/lib/stdlib/src/shell.erl
+++ b/lib/stdlib/src/shell.erl
@@ -228,10 +228,10 @@ server_loop(N0, Eval_0, Bs00, RT, Ds00, History0, Results0) ->
     N = N0 + 1,
     {Eval_1,Bs0,Ds0,Prompt} = prompt(N, Eval_0, Bs00, RT, Ds00),
     {Res,Eval0} = get_command(Prompt, Eval_1, Bs0, RT, Ds0),
+
     case Res of 
-	{ok,Es0,XBs} ->
-            Es1 = erl_eval:subst_values_for_vars(Es0, XBs),
-            case expand_hist(Es1, N) of
+	{ok,Es0} ->
+            case expand_hist(Es0, N) of
                 {ok,Es} ->
                     {V,Eval,Bs,Ds} = shell_cmd(Es, Eval0, Bs0, RT, Ds0, cmd),
                     {History,Results} = check_and_get_history_and_results(),
@@ -315,9 +315,9 @@ get_command1(Pid, Eval, Bs, RT, Ds) ->
 prompt(N, Eval0, Bs0, RT, Ds0) ->
     case get_prompt_func() of
         {M,F} ->
-            L = [{history,N}],
             A = erl_anno:new(1),
-            C = {call,A,{remote,A,{atom,A,M},{atom,A,F}},[{value,A,L}]},
+            L = {cons,A,{tuple,A,[{atom,A,history},{integer,A,N}]},{nil,A}},
+            C = {call,A,{remote,A,{atom,A,M},{atom,A,F}},[L]},
             {V,Eval,Bs,Ds} = shell_cmd([C], Eval0, Bs0, RT, Ds0, pmt),
             {Eval,Bs,Ds,case V of
                             {pmt,Val} ->
@@ -414,12 +414,12 @@ expand_expr({call,A,{atom,_,e},[N]}, C) ->
 	{Ces,_V,_CommandN} when is_list(Ces) ->
 	    {block,A,Ces}
     end;
-expand_expr({call,_A,{atom,_,v},[N]}, C) ->
+expand_expr({call,CA,{atom,VA,v},[N]}, C) ->
     case get_cmd(N, C) of
         {_,undefined,_} ->
 	    no_command(N);
-	{Ces,V,CommandN} when is_list(Ces) ->
-            {value,erl_anno:new(CommandN),V}
+	{Ces,_V,CommandN} when is_list(Ces) ->
+            {call,CA,{atom,VA,v},[{integer,VA,CommandN}]}
     end;
 expand_expr({call,A,F,Args}, C) ->
     {call,A,expand_expr(F, C),expand_exprs(Args, C)};
@@ -539,6 +539,9 @@ shell_rep(Ev, Bs0, RT, Ds0) ->
             fwrite_severity(benign, <<"~s: ~ts">>,
                             [pos(Location), M:format_error(Error)]),
             {{'EXIT',Error},Ev,Bs0,Ds0};
+        {shell_req,Ev,{get_cmd,N}} ->
+	    Ev ! {shell_rep,self(),getc(N)},
+	    shell_rep(Ev, Bs0, RT, Ds0);
 	{shell_req,Ev,get_cmd} ->
 	    Ev ! {shell_rep,self(),get()},
 	    shell_rep(Ev, Bs0, RT, Ds0);
@@ -956,6 +959,10 @@ init_dict([]) -> true.
 %% handled in this module (i.e. those that are not eventually handled by 
 %% non_builtin_local_func/3 (user_default/shell_default).
 
+local_func(v, [{integer,_,V}], Bs, Shell, _RT, _Lf, _Ef) ->
+    %% This command is validated and expanded prior.
+    {_Ces,Value,_N} = shell_req(Shell, {get_cmd, V}),
+    {value,Value,Bs};
 local_func(h, [], Bs, Shell, RT, _Lf, _Ef) ->
     Cs = shell_req(Shell, get_cmd),
     Cs1 = lists:filter(fun({{command, _},_}) -> true;
diff --git a/lib/stdlib/test/qlc_SUITE.erl b/lib/stdlib/test/qlc_SUITE.erl
index 3ab1c50332..416a12c211 100644
--- a/lib/stdlib/test/qlc_SUITE.erl
+++ b/lib/stdlib/test/qlc_SUITE.erl
@@ -7466,10 +7466,10 @@ etsc(F, Opts, Objs) ->
     V.
 
 join_info(H) ->
-    {{qlc, S, Options}, Bs} = strip_qlc_call2(H),
+    {qlc, S, Options} = strip_qlc_call(H),
     %% "Hide" the call to qlc_pt from the test in run_test().
     LoadedPT = code:is_loaded(qlc_pt),
-    QH = qlc:string_to_handle(S, Options, Bs),
+    QH = qlc:string_to_handle(S, Options, []),
     _ = [unload_pt() || false <- [LoadedPT]], % doesn't take long...
     case {join_info_count(H), join_info_count(QH)} of
         {N, N} -> 
@@ -7479,26 +7479,22 @@ join_info(H) ->
     end.
 
 strip_qlc_call(H) ->
-    {Expr, _Bs} = strip_qlc_call2(H),
-    Expr.
-
-strip_qlc_call2(H) ->
     S = qlc:info(H, {flat, false}),
     {ok, Tokens, _EndLine} = erl_scan:string(S++".", 1, [text]),
-    {ok, [Expr], Bs} = erl_eval:extended_parse_exprs(Tokens),
-    {case Expr of
-         {call,_,{remote,_,{atom,_,qlc},{atom,_,q}},[LC]} ->
-             {qlc, lists:flatten([erl_pp:expr(LC), "."]), []};
-         {call,_,{remote,_,{atom,_,qlc},{atom,_,q}},[LC, Opts]} ->
-             {qlc, lists:flatten([erl_pp:expr(LC), "."]),
-              erl_parse:normalise(Opts)};
-         {call,_,{remote,_,{atom,_,ets},{atom,_,match_spec_run}},_} ->
-             {match_spec, Expr};
-         {call,_,{remote,_,{atom,_,M},{atom,_,table}},_} ->
-             {table, M, Expr};
-         _ ->
-             []
-     end, Bs}.
+    {ok, [Expr]} = erl_eval:extended_parse_exprs(Tokens),
+    case Expr of
+        {call,_,{remote,_,{atom,_,qlc},{atom,_,q}},[LC]} ->
+            {qlc, lists:flatten([erl_pp:expr(LC), "."]), []};
+        {call,_,{remote,_,{atom,_,qlc},{atom,_,q}},[LC, Opts]} ->
+            {qlc, lists:flatten([erl_pp:expr(LC), "."]),
+             erl_parse:normalise(Opts)};
+        {call,_,{remote,_,{atom,_,ets},{atom,_,match_spec_run}},_} ->
+            {match_spec, Expr};
+        {call,_,{remote,_,{atom,_,M},{atom,_,table}},_} ->
+            {table, M, Expr};
+        _ ->
+            []
+    end.
 
 -record(ji, {nmerge = 0, nlookup = 0, nnested_loop = 0, nkeysort = 0}).
 
@@ -7506,7 +7502,7 @@ strip_qlc_call2(H) ->
 join_info_count(H) ->
     S = qlc:info(H, {flat, false}),    
     {ok, Tokens, _EndLine} = erl_scan:string(S++".", 1, [text]),
-    {ok, [Expr], _Bs} = erl_eval:extended_parse_exprs(Tokens),
+    {ok, [Expr]} = erl_eval:extended_parse_exprs(Tokens),
     #ji{nmerge = Nmerge, nlookup = Nlookup, 
         nkeysort = NKeysort, nnested_loop = Nnested_loop} = 
         ji(Expr, #ji{}),
@@ -7550,7 +7546,7 @@ lookup_keys({generate,_,Q}, L) ->
     lookup_keys(Q, L);
 lookup_keys({table,Chars}, L) when is_list(Chars) ->
     {ok, Tokens, _} = erl_scan:string(lists:flatten(Chars++"."), 1, [text]),
-    {ok, [Expr], _Bs} = erl_eval:extended_parse_exprs(Tokens),
+    {ok, [Expr]} = erl_eval:extended_parse_exprs(Tokens),
     case Expr of
         {call,_,_,[_fun,AKs]} ->
             case erl_parse:normalise(AKs) of
-- 
2.31.1

Places

File 2251-Remove-undocumented-value-Value-Ann-in-erl_eval.patch of Package erlang (Revision 371fc947ce89baa340e0441f200e4667)

Places