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CUnion[name,members]

is a symbolic representation of a union.

CUnion[name]

declares a union without specifying the contents.

CUnion[None,members]

does not give the union a name.

Details and Options
Details and Options Details and Options
Examples  
Basic Examples  
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SymbolicC`
SymbolicC`

CUnion

CUnion[name,members]

is a symbolic representation of a union.

CUnion[name]

declares a union without specifying the contents.

CUnion[None,members]

does not give the union a name.

Details and Options

  • SymbolicC expressions are inert; they evaluate to themselves, staying in an unevaluated form.
  • SymbolicC expressions can be converted into a C string with ToCCodeString.
  • The members of the union can be specified with lists or with CDeclare.

Examples

Basic Examples  (1)

To use SymbolicC, you first need to load the package:

Wolfram Language code: Needs["SymbolicC`"]

This creates a union:

Wolfram Language code: CUnion["data", {{"int", "ival"}, {"double", "dval"}}]//ToCCodeString

You can use CDeclare to declare the members of the union:

Wolfram Language code: CUnion["data", {CDeclare["int", "ival"], CDeclare["double", "dval"]}]//ToCCodeString

You can drop the name for the union by using a specification of None:

Wolfram Language code: CDeclare[ CUnion[None, {{"int", "ival"}, {"double", "dval"}}], "pt1"]//ToCCodeString

You can use an incomplete type with a typedef:

Wolfram Language code: CTypedef[ CUnion["data"], CDereference["d1"]]//ToCCodeString

You can nest a union inside a struct:

Wolfram Language code: CStruct["value", {{"int", "type"}, {CUnion[None, {{"int", "ival"}, {"double", "dval"}}], "data"}}]//ToCCodeString
Wolfram Research (2010), CUnion, Wolfram Language function, https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html.

Text

Wolfram Research (2010), CUnion, Wolfram Language function, https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html.

CMS

Wolfram Language. 2010. "CUnion." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html.

APA

Wolfram Language. (2010). CUnion. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html

BibTeX

@misc{reference.wolfram_2026_cunion, author="Wolfram Research", title="{CUnion}", year="2010", howpublished="\url{https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_cunion, organization={Wolfram Research}, title={CUnion}, year={2010}, url={https://reference.wolfram.com/language/SymbolicC/ref/CUnion.html}, note=[Accessed: 13-June-2026]}