# Arrays of functions

**URL:** <https://discourse.julialang.org/t/arrays-of-functions/46549>\
**Category:** New to Julia\
**Tags:** function\
**Created:** [September 13, 2020, 3:37pm UTC](https://discourse.julialang.org/t/arrays-of-functions/46549 "2020-09-13T15:37:19Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![simeonschaub](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/simeonschaub/32/216566_2.png) [@simeonschaub](https://discourse.julialang.org/u/simeonschaub)\
**Post date:** [September 13, 2020, 4:27pm UTC](https://discourse.julialang.org/t/arrays-of-functions/46549/6 "2020-09-13T16:27:24Z")

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You can actually really easily define `∘` yourself. In fact, this is exactly how it’s defined in Julia 1.5:

```julia
julia> f ∘ g = (x...) -> f(g(x...))
∘ (generic function with 1 method)

julia> f(x) = 2x + 1
f (generic function with 1 method)

julia> g(x) = x^2
g (generic function with 1 method)

julia> f ∘ g
#7 (generic function with 1 method)

julia> (f ∘ g)(3)
19

```

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