diff options
Diffstat (limited to 'doc/sphinx/language/gallina-extensions.rst')
| -rw-r--r-- | doc/sphinx/language/gallina-extensions.rst | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/doc/sphinx/language/gallina-extensions.rst b/doc/sphinx/language/gallina-extensions.rst index c21d8d4ec..8fbd2ea4e 100644 --- a/doc/sphinx/language/gallina-extensions.rst +++ b/doc/sphinx/language/gallina-extensions.rst @@ -23,8 +23,9 @@ expressions. In this sense, the :cmd:`Record` construction allows defining .. _record_grammar: .. productionlist:: `sentence` - record : `record_keyword` `ident` [ `binders` ] [: `sort` ] := [ `ident` ] { [ `field` ; … ; `field` ] }. + record : `record_keyword` `record_body` with … with `record_body` record_keyword : Record | Inductive | CoInductive + record_body : `ident` [ `binders` ] [: `sort` ] := [ `ident` ] { [ `field` ; … ; `field` ] }. field : `ident` [ `binders` ] : `type` [ where `notation` ] : | `ident` [ `binders` ] [: `type` ] := `term` @@ -167,12 +168,13 @@ and the syntax `term.(@qualid` |term_1| |term_n| `)` to `@qualid` |term_1| `…` In each case, `term` is the object projected and the other arguments are the parameters of the inductive type. + .. note:: Records defined with the ``Record`` keyword are not allowed to be recursive (references to the record's name in the type of its field raises an error). To define recursive records, one can use the ``Inductive`` and ``CoInductive`` keywords, resulting in an inductive or co-inductive record. - A *caveat*, however, is that records cannot appear in mutually inductive - (or co-inductive) definitions. + Definition of mutal inductive or co-inductive records are also allowed, as long + as all of the types in the block are records. .. note:: Induction schemes are automatically generated for inductive records. Automatic generation of induction schemes for non-recursive records @@ -2226,7 +2228,7 @@ existential variable used in the same context as its context of definition is wr Check (fun x y => _) 0 1. Existential variables can be named by the user upon creation using -the syntax ``?``\ `ident`. This is useful when the existential +the syntax :n:`?[@ident]`. This is useful when the existential variable needs to be explicitly handled later in the script (e.g. with a named-goal selector, see :ref:`goal-selectors`). |