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Tagged union

In computer science, a tagged union, also called a variant, variant record, choice type, discriminated union, disjoint union, sum type, or coproduct, is a data structure used to hold a value that could take on several different, but fixed, types. Only one of the types can be in use at any one time, and a tag field explicitly indicates which type is in…

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Description

Functional programmingML-styleHaskellConstructorCompiler
31 related topics

Language support

ALGOL 68AdaC++C++17Standard library
27 related topics

Advantages and disadvantages

RecordImmutableSentinel valuesType punningUniversal data type
9 related topics

Class hierarchies as tagged unions

Object-oriented programmingVirtual methodVtableRTTISubtype polymorphism
5 related topics

Topics to explore

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Overview

Description

Advantages and disadvantages

Examples

Language support

Class hierarchies as tagged unions

Advanced semantic analysis

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Map overview Semantic statistics

Tagged union

Nodes87
Edges86
Triples53
Avg. degree1.98
Density0.022989
Components1

How this topic connects Entity context

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Tagged union

Top relations

related to Class hierarchies as tagged unions · 9
Tagged union → An, Hence, In, It, Nevertheless, RTTI, Scala, Some, The
related to Description · 6
Tagged union → Compile-time, Haskell, ML, Rust, Tagged, They
related to Examples · 5
Tagged union → Leaf, ML, Node, The, This
related to Advantages and disadvantages · 4
Tagged union → Some, The, Untagged, When
related to C# · 3
Tagged union → The, Thedefaultvalue, With
related to C++ · 3
Tagged union → The, Ts, While
related to Rust · 3
Tagged union → For, It, The Rust
related to Cyclone · 2
Tagged union → Cyclone, These
related to Haxe · 2
Tagged union → Haxe's, These
related to Java · 2
Tagged union → In Java, Pattern

Important terminology Word statistics

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Important terminology

tagged type unions union types data tag value used class called may also handled case sum cases example pattern variant

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
MLinstance ofDescriptionTagged unions are most important in functional programming languages0.80text
Haskellinstance ofDescriptionTagged unions are most important in functional programming languages0.80text
where they are called datatypesinstance ofDescriptionTagged unions are most important in functional programming languages0.80text
Scala allow base classes to beinstance ofSome languages0.80text
Tagged unionrelated to Advantages and disadvantagesThe0.60section
Tagged unionrelated to Advantages and disadvantagesUntagged0.60section
Tagged unionrelated to Advantages and disadvantagesSome0.60section
Tagged unionrelated to Advantages and disadvantagesWhen0.60section
Tagged unionrelated to ALGOL 68In ALGOL0.60section
Tagged unionrelated to C#The0.60section
Tagged unionrelated to C#With0.60section
Tagged unionrelated to C#Thedefaultvalue0.60section

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    Min side: 3
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