VDM-10 Language Manual

Chapter 3. Data Type Definitions
m1 ++ { |-> 8,
|->
4}
merge{ { |-> 9,
|-> 4}
{ |-> 9,
|-> 3,
|->
1}}
≡ { |-> 8,
|-> 4,
|-> 2,
|-> 1,
|-> 4}
≡ { |-> 9,
|-> 3,
|-> 4,
|-> 1}
Europe 9,
|-> 4}
Europe 2,
|-> 1}
m1 :> {2,...,10} ≡ { |-> 9,
|-> 4,
|-> 2}
m1 :-> {2,...,10} ≡ { |-> 1}
m1 comp ({"France" |-> }) ≡ {"France" |-> 9}
m2 ** 3 ≡ {1 |-> 4, 2 |-> 1,
3 |-> 2, 4 |-> 3 }
inverse m2 ≡ {2 |-> 1, 3 |-> 2,
4 |-> 3, 1 |-> 4 }
m2 comp (inverse m2) ≡ {1 |-> 1, 2 |-> 2,
3 |-> 3, 4 |-> 4 }
3.2.4 Product Types
The values of a product type are called tuples. A tuple is a fixed length list where the i’th element
of the tuple must belong to the i’th element of the product type.
Syntax:
type = product type
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