File 2140-Support-map-comprehensions-in-syntax_tools.patch of Package erlang
From 246e08cdad39d836f73c2a9a42aaaa529d470c39 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= <bjorn@erlang.org>
Date: Tue, 24 Jan 2023 12:15:45 +0100
Subject: [PATCH 10/12] Support map comprehensions in syntax_tools
---
lib/syntax_tools/src/erl_prettypr.erl | 15 ++
lib/syntax_tools/src/erl_syntax.erl | 153 +++++++++++++++++-
.../syntax_tools_SUITE_test_module.erl | 11 +-
3 files changed, 177 insertions(+), 2 deletions(-)
diff --git a/lib/syntax_tools/src/erl_prettypr.erl b/lib/syntax_tools/src/erl_prettypr.erl
index d6c1c1e005..89ff4bf134 100644
--- a/lib/syntax_tools/src/erl_prettypr.erl
+++ b/lib/syntax_tools/src/erl_prettypr.erl
@@ -858,6 +858,12 @@ lay_2(Node, Ctxt) ->
D2 = lay(erl_syntax:binary_generator_body(Node), Ctxt1),
par([D1, beside(text("<= "), D2)], Ctxt1#ctxt.break_indent);
+ map_generator ->
+ Ctxt1 = reset_prec(Ctxt),
+ D1 = lay(erl_syntax:map_generator_pattern(Node), Ctxt1),
+ D2 = lay(erl_syntax:map_generator_body(Node), Ctxt1),
+ par([D1, beside(text("<- "), D2)], Ctxt1#ctxt.break_indent);
+
implicit_fun ->
D = lay(erl_syntax:implicit_fun_name(Node),
reset_prec(Ctxt)),
@@ -883,6 +889,15 @@ lay_2(Node, Ctxt) ->
par([D1, beside(floating(text(" || ")),
beside(D2, floating(text(" >>"))))]));
+ map_comp ->
+ Ctxt1 = set_prec(Ctxt, max_prec()),
+ D1 = lay(erl_syntax:map_comp_template(Node), Ctxt1),
+ D2 = par(seq(erl_syntax:map_comp_body(Node),
+ floating(text(",")), Ctxt1,
+ fun lay/2)),
+ beside(floating(text("#{")),
+ par([D1, beside(floating(text("|| ")),
+ beside(D2, floating(text("}"))))]));
macro ->
%% This is formatted similar to a normal function call, but
%% prefixed with a "?".
diff --git a/lib/syntax_tools/src/erl_syntax.erl b/lib/syntax_tools/src/erl_syntax.erl
index 4da1635aec..1958865b3b 100644
--- a/lib/syntax_tools/src/erl_syntax.erl
+++ b/lib/syntax_tools/src/erl_syntax.erl
@@ -246,6 +246,9 @@
macro/2,
macro_arguments/1,
macro_name/1,
+ map_comp/2,
+ map_comp_template/1,
+ map_comp_body/1,
map_expr/1,
map_expr/2,
map_expr_argument/1,
@@ -256,6 +259,9 @@
map_field_exact/2,
map_field_exact_name/1,
map_field_exact_value/1,
+ map_generator/2,
+ map_generator_body/1,
+ map_generator_pattern/1,
map_type/0,
map_type/1,
map_type_fields/1,
@@ -715,8 +721,10 @@ type(Node) ->
{function, _, _, _, _} -> function;
{b_generate, _, _, _} -> binary_generator;
{generate, _, _, _} -> generator;
+ {m_generate, _, _, _} -> map_generator;
{lc, _, _, _} -> list_comp;
- {bc, _, _, _} -> binary_comp;
+ {bc, _, _, _} -> binary_comp;
+ {mc, _, _, _} -> map_comp;
{match, _, _, _} -> match_expr;
{map, _, _, _} -> map_expr;
{map, _, _} -> map_expr;
@@ -6138,6 +6146,72 @@ binary_comp_body(Node) ->
(data(Node1))#binary_comp.body
end.
+%% =====================================================================
+%% @doc Creates an abstract map comprehension. If `Body' is
+%% `[E1, ..., En]', the result represents
+%% "<code>#{<em>Template</em> || <em>E1</em>, ..., <em>En</em>}</code>".
+%%
+%% @see map_comp_template/1
+%% @see map_comp_body/1
+%% @see generator/2
+
+-record(map_comp, {template :: syntaxTree(), body :: [syntaxTree()]}).
+
+%% type(Node) = map_comp
+%% data(Node) = #map_comp{template :: Template, body :: Body}
+%%
+%% Template = Node = syntaxTree()
+%% Body = [syntaxTree()]
+%%
+%% `erl_parse' representation:
+%%
+%% {mc, Pos, Template, Body}
+%%
+%% Template = erl_parse()
+%% Body = [erl_parse()] \ []
+
+-spec map_comp(syntaxTree(), [syntaxTree()]) -> syntaxTree().
+
+map_comp(Template, Body) ->
+ tree(map_comp, #map_comp{template = Template, body = Body}).
+
+revert_map_comp(Node) ->
+ Pos = get_pos(Node),
+ Template = map_comp_template(Node),
+ Body = map_comp_body(Node),
+ {mc, Pos, Template, Body}.
+
+
+%% =====================================================================
+%% @doc Returns the template subtree of a `map_comp' node.
+%%
+%% @see map_comp/2
+
+-spec map_comp_template(syntaxTree()) -> syntaxTree().
+
+map_comp_template(Node) ->
+ case unwrap(Node) of
+ {mc, _, Template, _} ->
+ Template;
+ Node1 ->
+ (data(Node1))#map_comp.template
+ end.
+
+
+%% =====================================================================
+%% @doc Returns the list of body subtrees of a `map_comp' node.
+%%
+%% @see map_comp/2
+
+-spec map_comp_body(syntaxTree()) -> [syntaxTree()].
+
+map_comp_body(Node) ->
+ case unwrap(Node) of
+ {mc, _, _, Body} ->
+ Body;
+ Node1 ->
+ (data(Node1))#map_comp.body
+ end.
%% =====================================================================
%% @doc Creates an abstract generator. The result represents
@@ -6271,6 +6345,72 @@ binary_generator_body(Node) ->
end.
+%% =====================================================================
+%% @doc Creates an abstract map_generator. The result represents
+%% "<code><em>Pattern</em> <- <em>Body</em></code>".
+%%
+%% @see map_generator_pattern/1
+%% @see map_generator_body/1
+%% @see list_comp/2
+%% @see map_comp/2
+
+-record(map_generator, {pattern :: syntaxTree(), body :: syntaxTree()}).
+
+%% type(Node) = map_generator
+%% data(Node) = #map_generator{pattern :: Pattern, body :: Body}
+%%
+%% Pattern = Argument = syntaxTree()
+%%
+%% `erl_parse' representation:
+%%
+%% {m_generate, Pos, Pattern, Body}
+%%
+%% Pattern = Body = erl_parse()
+
+-spec map_generator(syntaxTree(), syntaxTree()) -> syntaxTree().
+
+map_generator(Pattern, Body) ->
+ tree(map_generator, #map_generator{pattern = Pattern, body = Body}).
+
+revert_map_generator(Node) ->
+ Pos = get_pos(Node),
+ Pattern = map_generator_pattern(Node),
+ Body = map_generator_body(Node),
+ {m_generate, Pos, Pattern, Body}.
+
+
+%% =====================================================================
+%% @doc Returns the pattern subtree of a `generator' node.
+%%
+%% @see map_generator/2
+
+-spec map_generator_pattern(syntaxTree()) -> syntaxTree().
+
+map_generator_pattern(Node) ->
+ case unwrap(Node) of
+ {m_generate, _, Pattern, _} ->
+ Pattern;
+ Node1 ->
+ (data(Node1))#map_generator.pattern
+ end.
+
+
+%% =====================================================================
+%% @doc Returns the body subtree of a `generator' node.
+%%
+%% @see map_generator/2
+
+-spec map_generator_body(syntaxTree()) -> syntaxTree().
+
+map_generator_body(Node) ->
+ case unwrap(Node) of
+ {m_generate, _, _, Body} ->
+ Body;
+ Node1 ->
+ (data(Node1))#map_generator.body
+ end.
+
+
%% =====================================================================
%% @doc Creates an abstract block expression. If `Body' is
%% `[B1, ..., Bn]', the result represents "<code>begin
@@ -7724,12 +7864,16 @@ revert_root(Node) ->
revert_list(Node);
list_comp ->
revert_list_comp(Node);
+ map_comp ->
+ revert_map_comp(Node);
map_expr ->
revert_map_expr(Node);
map_field_assoc ->
revert_map_field_assoc(Node);
map_field_exact ->
revert_map_field_exact(Node);
+ map_generator ->
+ revert_map_generator(Node);
map_type ->
revert_map_type(Node);
map_type_assoc ->
@@ -8017,6 +8161,8 @@ subtrees(T) ->
As ->
[[macro_name(T)], As]
end;
+ map_comp ->
+ [[map_comp_template(T)], map_comp_body(T)];
map_expr ->
case map_expr_argument(T) of
none ->
@@ -8030,6 +8176,9 @@ subtrees(T) ->
map_field_exact ->
[[map_field_exact_name(T)],
[map_field_exact_value(T)]];
+ map_generator ->
+ [[map_generator_pattern(T)],
+ [map_generator_body(T)]];
map_type ->
[map_type_fields(T)];
map_type_assoc ->
@@ -8207,10 +8356,12 @@ make_tree(list, [P, [S]]) -> list(P, S);
make_tree(list_comp, [[T], B]) -> list_comp(T, B);
make_tree(macro, [[N]]) -> macro(N);
make_tree(macro, [[N], A]) -> macro(N, A);
+make_tree(map_comp, [[T], B]) -> map_comp(T, B);
make_tree(map_expr, [Fs]) -> map_expr(Fs);
make_tree(map_expr, [[E], Fs]) -> map_expr(E, Fs);
make_tree(map_field_assoc, [[K], [V]]) -> map_field_assoc(K, V);
make_tree(map_field_exact, [[K], [V]]) -> map_field_exact(K, V);
+make_tree(map_generator, [[P], [E]]) -> map_generator(P, E);
make_tree(map_type, [Fs]) -> map_type(Fs);
make_tree(map_type_assoc, [[N],[V]]) -> map_type_assoc(N, V);
make_tree(map_type_exact, [[N],[V]]) -> map_type_exact(N, V);
diff --git a/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_SUITE_test_module.erl b/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_SUITE_test_module.erl
index 9035139fea..daa95b6a25 100644
--- a/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_SUITE_test_module.erl
+++ b/lib/syntax_tools/test/syntax_tools_SUITE_data/syntax_tools_SUITE_test_module.erl
@@ -8,7 +8,7 @@
sub_word/2,sub_word/3,left/2,left/3,right/2,right/3,
sub_string/2,sub_string/3,centre/2,centre/3, join/2]).
-export([to_upper/1, to_lower/1]).
--export([eep49/0]).
+-export([eep49/0, eep58/0]).
-import(lists,[reverse/1,member/2]).
@@ -581,3 +581,12 @@ eep49() ->
end,
ok.
+
+%% EEP-58: Map comprehensions.
+eep58() ->
+ Seq = lists:seq(1, 10),
+ Map = #{{key,I} => I || I <- Seq},
+ MapDouble = #{K => 2 * V || K := V <- Map},
+ MapDouble = maps:from_list([{{key,I}, 2 * I} || I <- Seq]),
+
+ ok.
--
2.35.3