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.. _traditional-record-syntax:
Traditional record syntax
-------------------------
.. extension:: NoTraditionalRecordSyntax
:shortdesc: Disable support for traditional record syntax
(as supported by Haskell 98) ``C {f = x}``
:since: 7.4.1
Disallow use of record syntax.
Traditional record syntax, such as ``C {f = x}``, is enabled by default.
To disable it, you can use the :extension:`NoTraditionalRecordSyntax` extension.
Under :extension:`NoTraditionalRecordSyntax`, it is not permitted to define a
record datatype or use record syntax in an expression. For example, the
following all require :extension:`TraditionalRecordSyntax`:
.. code-block:: haskell
data T = MkT { foo :: Int } -- record datatype definition
x = MkT { foo = 3 } -- construction
y = x { foo = 3 } -- update
f (MkT { foo = i }) = i -- pattern matching
However, if a field selector function is in scope, it may be used normally.
(This arises if a module using :extension:`NoTraditionalRecordSyntax` imports a
module that defined a record with :extension:`TraditionalRecordSyntax` enabled).
If you wish to suppress field selector functions, use the
:extension:`NoFieldSelectors` extension.
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