[stdlib] Add new SDTLIB application variable 'shell_strings'

Use the new function shell:strings/1 to toggle how the Erlang shell
outputs lists of integers.

3 files changed, 29 insertions, 12 deletions

diff --git a/lib/stdlib/src/io_lib_format.erl b/lib/stdlib/src/io_lib_format.erl
index 19eccf9355..56e15a17ec 100644
--- a/lib/stdlib/src/io_lib_format.erl
+++ b/lib/stdlib/src/io_lib_format.erl
@@ -58,7 +58,7 @@ collect_cseq(Fmt0, Args0) ->
     {P,Fmt2,Args2} = precision(Fmt1, Args1),
     {Pad,Fmt3,Args3} = pad_char(Fmt2, Args2),
     {Encoding,Fmt4,Args4} = encoding(Fmt3, Args3),
-    {Strings,Fmt5,Args5} = pretty_lists(Fmt4, Args4),
+    {Strings,Fmt5,Args5} = strings(Fmt4, Args4),
     {C,As,Fmt6,Args6} = collect_cc(Fmt5, Args5),
     {{C,As,F,Ad,P,Pad,Encoding,Strings},Fmt6,Args6}.
 
@@ -68,11 +68,11 @@ encoding([$t|Fmt],Args) ->
 encoding(Fmt,Args) ->
     {latin1,Fmt,Args}.
 
-pretty_lists([$l|Fmt],Args) ->
+strings([$l|Fmt],Args) ->
     true = hd(Fmt) =/= $t,
-    {no,Fmt,Args};
-pretty_lists(Fmt,Args) ->
-    {unicode,Fmt,Args}.
+    {false,Fmt,Args};
+strings(Fmt,Args) ->
+    {true,Fmt,Args}.
 
 field_width([$-|Fmt0], Args0) ->
     {F,Fmt,Args} = field_value(Fmt0, Args0),
diff --git a/lib/stdlib/src/io_lib_pretty.erl b/lib/stdlib/src/io_lib_pretty.erl
index c7d2ad97c7..525b534249 100644
--- a/lib/stdlib/src/io_lib_pretty.erl
+++ b/lib/stdlib/src/io_lib_pretty.erl
@@ -56,7 +56,7 @@ print(Term) ->
                 | {depth, depth()}
                 | {max_chars, max_chars()}
                 | {record_print_fun, rec_print_fun()}
-                | {strings, io_lib:pretty_lists()}
+                | {strings, boolean()}
                 | {encoding, latin1 | utf8 | unicode}.
 -type options() :: [option()].
 
@@ -332,7 +332,7 @@ print_length([], _D, _RF, _Enc, _Str) ->
 print_length({}, _D, _RF, _Enc, _Str) ->
     {"{}", 2};
 print_length(List, D, RF, Enc, Str) when is_list(List) ->
-    case Str =:= unicode andalso printable_list(List, D, Enc) of
+    case Str andalso printable_list(List, D, Enc) of
         true ->
             S = write_string(List, Enc),
             {S, length(S)};
@@ -364,7 +364,7 @@ print_length(<<_/bitstring>>=Bin, D, _RF, Enc, Str) ->
     case bit_size(Bin) rem 8 of
         0 ->
 	    D1 = D - 1, 
-	    case Str =:= unicode andalso printable_bin(Bin, D1, Enc) of
+	    case Str andalso printable_bin(Bin, D1, Enc) of
                 {true, List} when is_list(List) ->
                     S = io_lib:write_string(List, $"), %"
 	            {[$<,$<,S,$>,$>], 4 + length(S)};
diff --git a/lib/stdlib/src/shell.erl b/lib/stdlib/src/shell.erl
index c94f052b24..df66acb97b 100644
--- a/lib/stdlib/src/shell.erl
+++ b/lib/stdlib/src/shell.erl
@@ -22,7 +22,7 @@
 -export([whereis_evaluator/0, whereis_evaluator/1]).
 -export([start_restricted/1, stop_restricted/0]).
 -export([local_allowed/3, non_local_allowed/3]).
--export([prompt_func/1]).
+-export([prompt_func/1, strings/1]).
 
 -define(LINEMAX, 30).
 -define(CHAR_MAX, 60).
@@ -30,6 +30,7 @@
 -define(DEF_RESULTS, 20).
 -define(DEF_CATCH_EXCEPTION, false).
 -define(DEF_PROMPT_FUNC, default).
+-define(DEF_STRINGS, true).
 
 -define(RECORDS, shell_records).
 
@@ -1366,8 +1367,16 @@ pp(V, I, RT) ->
     pp(V, I, RT, enc()).
 
 pp(V, I, RT, Enc) ->
+    Strings =
+        case application:get_env(stdlib, shell_strings) of
+            {ok, false} ->
+                false;
+            _ ->
+                true
+        end,
     io_lib_pretty:print(V, ([{column, I}, {line_length, columns()},
                              {depth, ?LINEMAX}, {max_chars, ?CHAR_MAX},
+                             {strings, Strings},
                              {record_print_fun, record_print_fun(RT)}]
                             ++ Enc)).
 
@@ -1444,14 +1453,22 @@ history(L) when is_integer(L), L >= 0 ->
 results(L) when is_integer(L), L >= 0 ->
     set_env(stdlib, shell_saved_results, L, ?DEF_RESULTS).
 
--spec catch_exception(Bool) -> Bool when
+-spec catch_exception(Bool) -> boolean() when
       Bool :: boolean().
 
 catch_exception(Bool) ->
     set_env(stdlib, shell_catch_exception, Bool, ?DEF_CATCH_EXCEPTION).
 
--spec prompt_func(PromptFunc) -> PromptFunc when
-      PromptFunc :: 'default' | {module(),atom()}.
+-spec prompt_func(PromptFunc) -> PromptFunc2 when
+      PromptFunc :: 'default' | {module(),atom()},
+      PromptFunc2 :: 'default' | {module(),atom()}.
 
 prompt_func(String) ->
     set_env(stdlib, shell_prompt_func, String, ?DEF_PROMPT_FUNC).
+
+-spec strings(Strings) -> Strings2 when
+      Strings :: boolean(),
+      Strings2 :: boolean().
+
+strings(Strings) ->
+    set_env(stdlib, shell_strings, Strings, ?DEF_STRINGS).