VDM-10 Language Manual

A.6.2
A.6.3
A.6.4
The VDM-SL State Definition
state definition = ‘state’, identifier, ‘of’, field list,
[ invariant ], [ initialisation ], ‘end’, [ ‘;’ ] ;
invariant = ‘inv’, invariant initial function ;
initialisation = ‘init’, invariant initial function ;
invariant initial function = pattern, ‘==’, expression ;
Value Definitions
value definitions = ‘values’, [ access value definition ],
{ ‘;’, access value definition }, [ ‘;’ ] ;
VDM-10 Language Manual
access value definition = ([ access ], [ ‘static’ ]) | ([ ‘static’ ], [ access ]),
value definition ;
value definition = pattern, [ ‘:’, type ], ‘=’, expression ;
Function Definitions
function definitions = ‘functions’, [ access function definition ],
{ ‘;’, access function definition }, [ ‘;’ ] ;
access function definition = [ access ], function definition ;
function definition = explicit function definition
| implicit function definition
| extended explicit function definition ;
explicit function definition = identifier, [ type variable list ], ‘:’,
function type,
identifier, parameters list,
‘==’, function body,
[ ‘pre’, expression ] ,
[ ‘post’, expression ],
[ ‘measure’, name ] ;
implicit function definition = identifier, [ type variable list ],
parameter types,
identifier type pair list,
[ ‘pre’, expression ],
‘post’, expression ;
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