From 9aac2420d3840873928e2af29452b0cca5e60ff1 Mon Sep 17 00:00:00 2001
From: lucdanton <lucdanton@free.fr>
Date: Wed, 25 Oct 2017 22:41:42 +0200
Subject: [PATCH] C++: remove function concepts.

---
 CHANGES                  |  1 +
 doc/domains.rst          | 17 +++--------------
 sphinx/domains/cpp.py    | 26 ++++----------------------
 tests/test_domain_cpp.py |  4 ----
 4 files changed, 8 insertions(+), 40 deletions(-)

diff --git a/CHANGES b/CHANGES
index 1d10d01fd..ebeffec52 100644
--- a/CHANGES
+++ b/CHANGES
@@ -68,6 +68,7 @@ Features removed
 * ``sphinx.util.nodes.process_only_nodes()``
 * LaTeX environment ``notice``, use ``sphinxadmonition`` instead
 * LaTeX ``\sphinxstylethead``, use ``\sphinxstyletheadfamily``
+* C++, support of function concepts
 
 Bugs fixed
 ----------
diff --git a/doc/domains.rst b/doc/domains.rst
index 1697c6605..e6a860bcd 100644
--- a/doc/domains.rst
+++ b/doc/domains.rst
@@ -720,13 +720,12 @@ a visibility statement (``public``, ``private`` or ``protected``).
 
 
 .. rst:directive:: .. cpp:concept:: template-parameter-list name
-                   .. cpp:concept:: template-parameter-list name()
 
    .. warning:: The support for concepts is experimental. It is based on the
       Concepts Technical Specification, and the features may change as the TS evolves.
 
-   Describe a variable concept or a function concept. Both must have exactly 1
-   template parameter list. The name may be a nested name. Examples::
+   Describe a concept. It must have exactly 1 template parameter list. The name may be a
+   nested name. Example::
 
       .. cpp:concept:: template<typename It> std::Iterator
 
@@ -744,12 +743,7 @@ a visibility statement (``public``, ``private`` or ``protected``).
          - :cpp:expr:`*r`, when :cpp:expr:`r` is dereferenceable.
          - :cpp:expr:`++r`, with return type :cpp:expr:`It&`, when :cpp:expr:`r` is incrementable.
 
-      .. cpp:concept:: template<typename Cont> std::Container()
-
-         Holder of elements, to which it can provide access via
-         :cpp:concept:`Iterator` s.
-
-   They will render as follows:
+   This will render as follows:
 
    .. cpp:concept:: template<typename It> std::Iterator
 
@@ -767,11 +761,6 @@ a visibility statement (``public``, ``private`` or ``protected``).
       - :cpp:expr:`*r`, when :cpp:expr:`r` is dereferenceable.
       - :cpp:expr:`++r`, with return type :cpp:expr:`It&`, when :cpp:expr:`r` is incrementable.
 
-   .. cpp:concept:: template<typename Cont> std::Container()
-
-      Holder of elements, to which it can provide access via
-      :cpp:concept:`Iterator` s.
-
 Options
 .......
 
diff --git a/sphinx/domains/cpp.py b/sphinx/domains/cpp.py
index 1db374205..a1b0a71c3 100644
--- a/sphinx/domains/cpp.py
+++ b/sphinx/domains/cpp.py
@@ -224,13 +224,12 @@ logger = logging.getLogger(__name__)
     concept_object:
         goal:
             just a declaration of the name (for now)
-            either a variable concept or function concept
 
         grammar: only a single template parameter list, and the nested name
             may not have any template argument lists
 
             "template" "<" template-parameter-list ">"
-            nested-name-specifier "()"[opt]
+            nested-name-specifier
 
     type_object:
         goal:
@@ -2780,10 +2779,9 @@ class ASTTypeUsing(ASTBase):
 
 
 class ASTConcept(ASTBase):
-    def __init__(self, nestedName, isFunction, initializer):
-        # type: (Any, bool, Any) -> None
+    def __init__(self, nestedName, initializer):
+        # type: (Any, Any) -> None
         self.nestedName = nestedName
-        self.isFunction = isFunction  # otherwise it's a variable concept
         self.initializer = initializer
 
     @property
@@ -2800,18 +2798,13 @@ class ASTConcept(ASTBase):
     def __unicode__(self):
         # type: () -> unicode
         res = text_type(self.nestedName)
-        if self.isFunction:
-            res += "()"
         if self.initializer:
             res += text_type(self.initializer)
         return res
 
     def describe_signature(self, signode, mode, env, symbol):
         # type: (addnodes.desc_signature, unicode, BuildEnvironment, Symbol) -> None
-        signode += nodes.Text(text_type("bool "))
         self.nestedName.describe_signature(signode, mode, env, symbol)
-        if self.isFunction:
-            signode += nodes.Text("()")
         if self.initializer:
             self.initializer.describe_signature(signode, mode, env, symbol)
 
@@ -4718,20 +4711,9 @@ class DefinitionParser(object):
     def _parse_concept(self):
         # type: () -> ASTConcept
         nestedName = self._parse_nested_name()
-        isFunction = False
-
         self.skip_ws()
-        if self.skip_string('('):
-            isFunction = True
-            self.skip_ws()
-            if not self.skip_string(')'):
-                self.fail("Expected ')' in function concept declaration.")
-
         initializer = self._parse_initializer('member')
-        if initializer and isFunction:
-            self.fail("Function concept with initializer.")
-
-        return ASTConcept(nestedName, isFunction, initializer)
+        return ASTConcept(nestedName, initializer)
 
     def _parse_class(self):
         # type: () -> ASTClass
diff --git a/tests/test_domain_cpp.py b/tests/test_domain_cpp.py
index 8c0fae2e3..63682237f 100644
--- a/tests/test_domain_cpp.py
+++ b/tests/test_domain_cpp.py
@@ -231,10 +231,6 @@ def test_concept_definitions():
           {2:'I0EN1A1B7ConceptE'})
     check('concept', 'template<typename A, typename B, typename ...C> Foo',
           {2:'I00DpE3Foo'})
-    check('concept', 'template<typename Param> A::B::Concept()',
-          {2:'I0EN1A1B7ConceptE'})
-    check('concept', 'template<typename A, typename B, typename ...C> Foo()',
-          {2:'I00DpE3Foo'})
     with pytest.raises(DefinitionError):
         parse('concept', 'Foo')
     with pytest.raises(DefinitionError):