VDM-10 Language Manual

A.9.2
A.9.3
A.9.4
Block and Assignment Statements
block statement = ‘(’, { dcl statement },
statement, { ‘;’, statement }, [ ‘;’ ], ‘)’ ;
dcl statement = ‘dcl’, assignment definition,
{ ‘,’, assignment definition }, ‘;’ ;
assignment definition = identifier, ‘:’, type, [ ‘:=’, expression ] ;
general assign statement = assign statement
| multiple assign statement ;
assign statement = state designator, ‘:=’, expression ;
multiple assign statement = ‘atomic’, ‘(’ assign statement, ‘;’,
assign statement,
[ { ‘;’, assign statement } ], ‘)’ ;
Conditional Statements
if statement = ‘if’, expression, ‘then’, statement,
{ elseif statement },
[ ‘else’, statement ] ;
elseif statement = ‘elseif’, expression, ‘then’, statement ;
cases statement = ‘cases’, expression, ‘:’,
cases statement alternatives,
[ ‘,’, others statement ], ‘end’ ;
cases statement alternatives = cases statement alternative,
{ ‘,’, cases statement alternative } ;
cases statement alternative = pattern list, ‘->’, statement ;
others statement = ‘others’, ‘->’, statement ;
Loop Statements
sequence for loop = ‘for’, pattern bind, ‘in’,
expression, ‘do’, statement ;
set for loop = ‘for’, ‘all’, pattern, ‘in set’, expression,
‘do’, statement ;
index for loop = ‘for’, identifier, ‘=’, expression, ‘to’, expression,
[ ‘by’, expression ],
‘do’, statement ;
while loop = ‘while’, expression, ‘do’, statement ;
VDM-10 Language Manual
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