represents the
combinator.
CombinatorY
represents the
combinator.
Details
- The
combinator has the property that
is equal to
. - No transformations for CombinatorY are applied automatically.
- CombinatorY is output in StandardForm or TraditionalForm as
. This typeset form can be input using
cY
.
Examples
open all close allBasic Examples (1)
Apply the standard reduction rules of combinatory logic:
CombinatorYf /. AxiomaticTheory["CombinatorAxioms", "RewriteRules"]f(CombinatorYf)These reduction rules do not terminate:
Nest[ReplaceAll[CombinatorYf_ :> f(CombinatorYf)], CombinatorYf, 10]Properties & Relations (1)
The
combinator can be expressed in terms of
,
and
in many ways:
cU = CombinatorS(CombinatorK(CombinatorSCombinatorI))(CombinatorSCombinatorICombinatorI);
cY = cUcUNest[ReplaceAll[{CombinatorSx_y_z_ :> xz(yz), CombinatorKx_y_ :> x, CombinatorIx_ :> x}], cYf, 4 * 2]See Also
Application CombinatorS CombinatorK FixedPoint
Function Repository: CombinatorConvert CombinatorTraditionalForm
Related Guides
History
Text
Wolfram Research (2020), CombinatorY, Wolfram Language function, https://reference.wolfram.com/language/ref/CombinatorY.html.
CMS
Wolfram Language. 2020. "CombinatorY." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/CombinatorY.html.
APA
Wolfram Language. (2020). CombinatorY. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CombinatorY.html
BibTeX
@misc{reference.wolfram_2026_combinatory, author="Wolfram Research", title="{CombinatorY}", year="2020", howpublished="\url{https://reference.wolfram.com/language/ref/CombinatorY.html}", note=[Accessed: 12-June-2026]}
BibLaTeX
@online{reference.wolfram_2026_combinatory, organization={Wolfram Research}, title={CombinatorY}, year={2020}, url={https://reference.wolfram.com/language/ref/CombinatorY.html}, note=[Accessed: 12-June-2026]}