VDM-10 Language Manual

Appendix A. The Syntax of the VDM Languages
function export = name list, [ type variable list ], ‘:’,
function type ;
functions signature = ‘functions’ function signature,
{ ‘;’, function signature }, [ ‘;’ ] ;
function signature = name list, ‘:’, function type ;
operations signature = ‘operations’ operation signature,
{ ‘;’, operation signature }, [ ‘;’ ] ;
operation signature = name list, ‘:’, operation type ;
A.3 VDM++ and VDM-RT Document
document = class | system , { class | system } ;
A.4 System (VDM-RT)
system = ‘system’, identifier,
[ class body ],
‘end’, identifier ;
A.5 Classes
class = ‘class’, identifier, [ inheritance clause ],
[ class body ],
‘end’, identifier ;
inheritance clause = ‘is subclass of’, identifier, ‘,’, { identifier } ;
A.6 Definitions
class body = definition block, { definition block } ;
module body = ‘definitions’, definition block, { definition block } ;
definition block = type definitions
| state definition
| value definitions
| function definitions
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