[attributes] Deprecate `attr(true)` syntax in favor of booelan attributes.

We introduce a warning so boolean attributes are expected to be of the
form `attr={yes,no}` or just `attr` (for `yes`).

We update the documentation, test-suite, and changelog.

7 files changed, 36 insertions, 46 deletions

diff --git a/doc/sphinx/language/core/basic.rst b/doc/sphinx/language/core/basic.rst
index 5406da38a1..af5c47dba8 100644
--- a/doc/sphinx/language/core/basic.rst
+++ b/doc/sphinx/language/core/basic.rst
@@ -379,6 +379,9 @@ this attribute`.
 The order of top-level attributes doesn't affect their meaning.  ``#[foo,bar]``, ``#[bar,foo]``,
 ``#[foo]#[bar]`` and ``#[bar]#[foo]`` are equivalent.
 
+Boolean attributes take the form ``attr={yes,no}``, when the key is
+omitted the default is assumed to be ``yes``.
+
 The legacy attributes (:n:`@legacy_attr`) provide an older, alternate syntax
 for certain attributes.  They are equivalent to new attributes as follows:
 
@@ -388,9 +391,9 @@ Legacy attribute  New attribute
 `Local`           :attr:`local`
 `Global`          :attr:`global`
 `Polymorphic`     :attr:`universes(polymorphic)`
-`Monomorphic`     :attr:`universes(monomorphic)`
+`Monomorphic`     :attr:`universes(polymorphic)`
 `Cumulative`      :attr:`universes(cumulative)`
-`NonCumulative`   :attr:`universes(noncumulative)`
+`NonCumulative`   :attr:`universes(cumulative)`
 `Private`         :attr:`private(matching)`
 `Program`         :attr:`program`
 ================  ================================
diff --git a/doc/sphinx/language/core/coinductive.rst b/doc/sphinx/language/core/coinductive.rst
index 3e2ecdc0f0..43bbc8b40d 100644
--- a/doc/sphinx/language/core/coinductive.rst
+++ b/doc/sphinx/language/core/coinductive.rst
@@ -26,10 +26,8 @@ More information on co-inductive definitions can be found in
    For co-inductive types, the only elimination principle is case analysis.
 
    This command supports the :attr:`universes(polymorphic)`,
-   :attr:`universes(monomorphic)`, :attr:`universes(template)`,
-   :attr:`universes(notemplate)`, :attr:`universes(cumulative)`,
-   :attr:`universes(noncumulative)`, :attr:`private(matching)`
-   and :attr:`using` attributes.
+   :attr:`universes(template)`, :attr:`universes(cumulative)`,
+   :attr:`private(matching)`, and :attr:`using` attributes.
 
 .. example::
 
diff --git a/doc/sphinx/language/core/definitions.rst b/doc/sphinx/language/core/definitions.rst
index 79489c85f6..57771c9036 100644
--- a/doc/sphinx/language/core/definitions.rst
+++ b/doc/sphinx/language/core/definitions.rst
@@ -90,7 +90,7 @@ Section :ref:`typing-rules`.
    computation on :n:`@term`.
 
    These commands also support the :attr:`universes(polymorphic)`,
-   :attr:`universes(monomorphic)`, :attr:`program` (see :ref:`program_definition`),
+   :attr:`program` (see :ref:`program_definition`),
    :attr:`canonical` and :attr:`using` attributes.
 
    If :n:`@term` is omitted, :n:`@type` is required and Coq enters proof editing mode.
diff --git a/doc/sphinx/language/core/inductive.rst b/doc/sphinx/language/core/inductive.rst
index ad7d6f3963..b9453650eb 100644
--- a/doc/sphinx/language/core/inductive.rst
+++ b/doc/sphinx/language/core/inductive.rst
@@ -32,10 +32,8 @@ Inductive types
    proposition).
 
    This command supports the :attr:`universes(polymorphic)`,
-   :attr:`universes(monomorphic)`, :attr:`universes(template)`,
-   :attr:`universes(notemplate)`, :attr:`universes(cumulative)`,
-   :attr:`universes(noncumulative)` and :attr:`private(matching)`
-   attributes.
+   :attr:`universes(template)`, :attr:`universes(cumulative)`, and
+   :attr:`private(matching)` attributes.
 
    Mutually inductive types can be defined by including multiple :n:`@inductive_definition`\s.
    The :n:`@ident`\s are simultaneously added to the environment before the types of constructors are checked.
@@ -1058,8 +1056,8 @@ Conversion is preserved as any (partial) instance :math:`I_j~q_1 … q_r` or
    at level :math:`\Type` (without annotations or hiding it behind a
    definition) template polymorphic if possible.
 
-   This can be prevented using the :attr:`universes(notemplate)`
-   attribute.
+   This can be prevented using the :attr:`universes(template)`
+   attribute with the ``=no`` setting.
 
    Template polymorphism and full universe polymorphism (see Chapter
    :ref:`polymorphicuniverses`) are incompatible, so if the latter is
@@ -1079,9 +1077,9 @@ Conversion is preserved as any (partial) instance :math:`I_j~q_1 … q_r` or
 
 .. attr:: universes(template)
 
-   This attribute can be used to explicitly declare an inductive type
-   as template polymorphic, whether the :flag:`Auto Template
-   Polymorphism` flag is on or off.
+   This boolean attribute can be used to explicitly declare an
+   inductive type as template polymorphic, whether the :flag:`Auto
+   Template Polymorphism` flag is on or off.
 
    .. exn:: template and polymorphism not compatible
 
@@ -1094,11 +1092,9 @@ Conversion is preserved as any (partial) instance :math:`I_j~q_1 … q_r` or
       The attribute was used but the inductive definition does not
       satisfy the criterion to be template polymorphic.
 
-.. attr:: universes(notemplate)
-
-   This attribute can be used to prevent an inductive type to be
-   template polymorphic, even if the :flag:`Auto Template
-   Polymorphism` flag is on.
+   When ``universes(template=no)`` is used, it will prevent an
+   inductive type to be template polymorphic, even if the :flag:`Auto
+   Template Polymorphism` flag is on.
 
 In practice, the rule **Ind-Family** is used by Coq only when all the
 inductive types of the inductive definition are declared with an arity
diff --git a/doc/sphinx/language/core/records.rst b/doc/sphinx/language/core/records.rst
index e6df3ee9f5..7eedbcd59a 100644
--- a/doc/sphinx/language/core/records.rst
+++ b/doc/sphinx/language/core/records.rst
@@ -53,10 +53,8 @@ expressions. In this sense, the :cmd:`Record` construction allows defining
    :cmd:`Record` and :cmd:`Structure` are synonyms.
 
    This command supports the :attr:`universes(polymorphic)`,
-   :attr:`universes(monomorphic)`, :attr:`universes(template)`,
-   :attr:`universes(notemplate)`, :attr:`universes(cumulative)`,
-   :attr:`universes(noncumulative)` and :attr:`private(matching)`
-   attributes.
+   :attr:`universes(template)`, :attr:`universes(cumulative)`, and
+   :attr:`private(matching)` attributes.
 
 More generally, a record may have explicitly defined (a.k.a. manifest)
 fields. For instance, we might have:
diff --git a/doc/sphinx/language/core/variants.rst b/doc/sphinx/language/core/variants.rst
index 645986be9c..6ac6626dbe 100644
--- a/doc/sphinx/language/core/variants.rst
+++ b/doc/sphinx/language/core/variants.rst
@@ -17,10 +17,8 @@ Variants
    this variant, unless the :flag:`Nonrecursive Elimination Schemes` flag is on.
 
    This command supports the :attr:`universes(polymorphic)`,
-   :attr:`universes(monomorphic)`, :attr:`universes(template)`,
-   :attr:`universes(notemplate)`, :attr:`universes(cumulative)`,
-   :attr:`universes(noncumulative)` and :attr:`private(matching)`
-   attributes.
+   :attr:`universes(template)`, :attr:`universes(cumulative)`, and
+   :attr:`private(matching)` attributes.
 
    .. exn:: The @natural th argument of @ident must be @ident in @type.
       :undocumented:
diff --git a/doc/sphinx/language/extensions/canonical.rst b/doc/sphinx/language/extensions/canonical.rst
index 48120503af..ec3e3e8aa6 100644
--- a/doc/sphinx/language/extensions/canonical.rst
+++ b/doc/sphinx/language/extensions/canonical.rst
@@ -87,29 +87,26 @@ in :ref:`canonicalstructures`; here only a simple example is given.
       If a same field occurs in several canonical structures, then
       only the structure declared first as canonical is considered.
 
-   .. attr:: canonical(false)
-
-      To prevent a field from being involved in the inference of
-      canonical instances, its declaration can be annotated with the
-      :attr:`canonical(false)` attribute (cf. the syntax of
-      :n:`@record_field`).
+.. attr:: canonical
 
-      .. example::
+   This boolean attribute can decorate a :cmd:`Definition` or
+   :cmd:`Let` command.  It is equivalent to having a :cmd:`Canonical
+   Structure` declaration just after the command.
 
-         For instance, when declaring the :g:`Setoid` structure above, the
-         :g:`Prf_equiv` field declaration could be written as follows.
+   To prevent a field from being involved in the inference of
+   canonical instances, its declaration can be annotated with
+   ``canonical=no`` (cf. the syntax of :n:`@record_field`).
 
-         .. coqdoc::
+   .. example::
 
-            #[canonical(false)] Prf_equiv : equivalence Carrier Equal
+      For instance, when declaring the :g:`Setoid` structure above, the
+      :g:`Prf_equiv` field declaration could be written as follows.
 
-      See :ref:`canonicalstructures` for a more realistic example.
+      .. coqdoc::
 
-.. attr:: canonical
+         #[canonical=no] Prf_equiv : equivalence Carrier Equal
 
-   This attribute can decorate a :cmd:`Definition` or :cmd:`Let` command.
-   It is equivalent to having a :cmd:`Canonical Structure` declaration just
-   after the command.
+   See :ref:`canonicalstructures` for a more realistic example.
 
 .. cmd:: Print Canonical Projections {* @reference }
 
@@ -331,7 +328,7 @@ We need to define a new class that inherits from both ``EQ`` and ``LE``.
                         LE_class : LE.class T;
                         extra : mixin (EQ.Pack T EQ_class) (LE.cmp T LE_class) }.
 
-    Structure type := _Pack { obj : Type; #[canonical(false)] class_of : class obj }.
+    Structure type := _Pack { obj : Type; #[canonical=no] class_of : class obj }.
 
     Arguments Mixin {e le} _.