VDM-10 Language Manual

VDM-10 Language Manual
element of the sequence. If the upper bound n2 is larger than the length of the sequence (the
largest index which can be used for a non-empty sequence) the subsequence expression will
end at the last element of the sequence.
Examples: Given that GroupA is equal to the sequence
✞
✡✝
[ mk_Score(,2,0,1,6),
mk_Score(,1,2,0,5),
mk_Score(,1,1,1,4),
mk_Score(,0,1,2,1) ]
✆
then:
[GroupA(i).team
| i in set inds GroupA
& GroupA(i).won 0]
[GroupA(i)
| i in set inds GroupA
& GroupA(i).won = 0]
≡
≡
[,
,
]
[mk Score(,0,1,2,1)]
GroupA(1,...,2) ≡ [mk Score(,2,0,1,6),
mk Score(,1,2,0,5)]
[GroupA(i)
| i in set inds GroupA
& GroupA(i).points = 9]
≡ []
6.9 Map Expressions
Syntax: expression = . . .
| map enumeration
| map comprehension
| . . . ;
map enumeration = ‘{’, maplet, { ‘,’, maplet }, ‘}’
| ‘{’, ‘|->’, ‘}’ ;
maplet = expression, ‘|->’, expression ;
map comprehension = ‘{’, maplet, ‘|’, bind list,
[ ‘&’, expression ], ‘}’ ;
Semantics: A map enumeration has the form:
✞
{d1 |-> r1, d2 |-> r2, ..., dn |-> rn}
✡✝
✆
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