VDM-10 Language Manual

VDM-10 Language Manual
| req expression
| waiting expression
| time expression
| name
| old name
| symbolic literal ;
A.7.1
A.7.2
Bracketed Expressions
bracketed expression = ‘(’, expression, ‘)’ ;
Local Binding Expressions
let expression = ‘let’, local definition, { ‘,’, local definition },
‘in’, expression ;
let be expression = ‘let’, multiple bind, [ ‘be’, ‘st’, expression ], ‘in’,
expression ;
def expression = ‘def’, pattern bind, ‘=’, expression,
{ ‘;’, pattern bind, ‘=’, expression }, [ ‘;’ ],
‘in’, expression ;
A.7.3
Conditional Expressions
if expression = ‘if’, expression, ‘then’, expression,
{ elseif expression },
‘else’, expression ;
elseif expression = ‘elseif’, expression, ‘then’, expression ;
cases expression = ‘cases’, expression, ‘:’,
cases expression alternatives,
[ ‘,’, others expression ], ‘end’ ;
cases expression alternatives = cases expression alternative,
{ ‘,’, cases expression alternative } ;
cases expression alternative = pattern list, ‘->’, expression ;
others expression = ‘others’, ‘->’, expression ;
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