# function composition
**URL:** https://forum.kx.com/t/function-composition/9139
**Category:** Community Support
**Tags:** kdb-and-q
**Created:** [October 8, 2014, 4:08am UTC](https://forum.kx.com/t/function-composition/9139 "2014-10-08T04:08:00Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@denghao8888](https://forum.kx.com/u/denghao8888)
#### Post date: [October 8, 2014, 4:08am UTC](https://forum.kx.com/t/function-composition/9139/1 "2014-10-08T04:08:00Z")
Hello:
Is there a way to compose two function f,g without using {}?
I know (2+3-) is a composition. But I failed to define composition of (inc inc) where inc:(1+)
Thanks in advance.
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### Author:  [@charlie1](https://forum.kx.com/u/charlie1)
#### Post date: [October 8, 2014, 4:31am UTC](https://forum.kx.com/t/function-composition/9139/2 "2014-10-08T04:31:00Z")
q)inc:(1+)
q)(inc inc@)2
4
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### Author:  [@kuentang](https://forum.kx.com/u/kuentang)
#### Post date: [October 8, 2014, 4:39am UTC](https://forum.kx.com/t/function-composition/9139/3 "2014-10-08T04:39:00Z")
q)f:{[w;x;y;z]w+x+y+z}\\
q)g:{2\*x}\\
q)h:(‘[g;f]) / The interpreter is finicky about :’\\
q)h[1;2;3;4]\\
20\\
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HTH,\\
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Kim\\
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**Von:** [personal-kdbplus@googlegroups.com](mailto:personal-kdbplus@googlegroups.com) [[mailto:personal-kdbplus@googlegroups.com](mailto:personal-kdbplus@googlegroups.com)] **Im Auftrag von** Hao Deng
**Gesendet:** Mittwoch, 8. Oktober 2014 11:09
**An:** [personal-kdbplus@googlegroups.com](mailto:personal-kdbplus@googlegroups.com)
**Betreff:** [personal kdb+] function composition\\
\ \
Hello:\\
Is there a way to compose two function f,g without using {}?\\
I know (2+3-) is a composition. But I failed to define composition of (inc inc) where inc:(1+)\\
\ \
Thanks in advance.\\
\ \
–
Submitted via Google Groups
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### Author:  [@denghao8888](https://forum.kx.com/u/denghao8888)
#### Post date: [October 8, 2014, 2:25pm UTC](https://forum.kx.com/t/function-composition/9139/4 "2014-10-08T14:25:00Z")
Thank you both Charles and Kim:
Both usage are not documents in [http://code.kx.com/wiki/Reference](http://code.kx.com/wiki/Reference) and anywhere I can find.
Did I missed any documents?
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### Author:  [@charlie1](https://forum.kx.com/u/charlie1)
#### Post date: [October 8, 2014, 2:45pm UTC](https://forum.kx.com/t/function-composition/9139/5 "2014-10-08T14:45:00Z")
http://code.kx.com/wiki/Reference/Apostrophe
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### Author:  [@denghao8888](https://forum.kx.com/u/denghao8888)
#### Post date: [October 8, 2014, 3:50pm UTC](https://forum.kx.com/t/function-composition/9139/6 "2014-10-08T15:50:00Z")
Thanks Charles.
I don’t understand the @ part.
I understand inc@ is a curry (project) of @,
but how does inc inc@ get parsed? Is this a special form?
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### Author:  [@charlie1](https://forum.kx.com/u/charlie1)
#### Post date: [October 13, 2014, 11:28am UTC](https://forum.kx.com/t/function-composition/9139/7 "2014-10-13T11:28:00Z")
juxtaposition is implicit apply
q)x:`a`b`c`d
q)x@2 3
`c`d
q)x 2 3
`c`d
if there’s no juxtaposition, i.e. no rhs, and you don’t want immediate evaluation, you have to explicitly insert an infix verb as the terminating token.
btw, you can pull compositions apart with value. e.g.
value(inc inc@)