Difference between revisions of "Union"
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+ | The semantics of Union are those common to C++ unions and Ada discriminated records. | ||
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+ | Typically the fields of a union are all physically allocated at the same address. As a result, the size of the union is the size of the largest of its fields. | ||
== Specification == | == Specification == | ||
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! Extends | ! Extends | ||
− | | [[Classfier]] [[StructuredType]] | + | | [[Classfier]], [[StructuredType]] |
|- | |- | ||
! Description | ! Description | ||
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|} | |} | ||
− | + | == Language Mappings == | |
− | + | Union maps to the C++ concept of union. A discriminated union corresponds to an Ada discriminated record. | |
Latest revision as of 15:01, 5 March 2014
The semantics of Union are those common to C++ unions and Ada discriminated records.
Typically the fields of a union are all physically allocated at the same address. As a result, the size of the union is the size of the largest of its fields.
Specification
Metaclass | Union |
---|---|
Extends | Classfier, StructuredType |
Description | A structure that stores the value of exactly one of a set of fields at any given time |
Language Mappings
Union maps to the C++ concept of union. A discriminated union corresponds to an Ada discriminated record.