# Why are the types in this example different?

**URL:** <https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [February 6, 2024, 2:21pm UTC](https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811 "2024-02-06T14:21:30Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Daniel\_Lincke](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/daniel_lincke/32/206206_2.png) [@Daniel\_Lincke](https://discourse.julialang.org/u/Daniel_Lincke)\
**Post date:** [February 6, 2024, 2:21pm UTC](https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811/1 "2024-02-06T14:21:30Z")

</div>

f0(x :: Float32) = 1f0

f1(p :: Float32) = function(x :: Float32);  
return (x+p)  
end

println(typeof([f0,f1(1.0f0)]))  
println(typeof([f1(0.0f0),f1(1.0f0)]))

this results in  
Vector{Function}  
Vector{var"#1#2"{Float32}}

why? And:

function foo(v::Vector{Function})  
println(“foo with Vector{Function}”)  
end

function foo(v::Vector{Any})  
println(“foo with Vector{Any}”)  
end

foo([f0,f1(1.0f0)])  
foo([f1(0.0f0),f1(1.0f0)])

results in  
foo with Vector{Function}  
ERROR: LoadError: MethodError: no method matching foo(::Vector{var"#1#2"{Float32}})

Again: why? and how tow fix the foo function so that foo([f1(0.0f0),f1(1.0f0)]) works (wtihout using convert in the function call)?

Tanks.

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [February 6, 2024, 2:33pm UTC](https://discourse.julialang.org/t/why-are-the-types-in-this-example-different/109811/2 "2024-02-06T14:33:39Z")

</div>

To your first question:

```julia
julia> typeof(f1(1f0)) == typeof(f1(0f0))
true

julia> typeof(f1(1f0)) == typeof(f0)
false

```

The `[]` tries to create a vector of the smallest possible type, and with all `f1` functions it can use this type. `f0` is of a different type (as all functions are their own type) so it has to punt to the supertype. This is the same as:

```julia
julia> typeof([sin, sin])
Vector{typeof(sin)} 

julia> typeof([sin, cos])
Vector{Function} 

```

On your second question you are probably looking for

```julia
julia> function foo(v::Vector{<:Any})
       println("foo with Vector{Any}")
       end
foo (generic function with 3 methods)

julia> foo([f1(0.0f0),f1(1.0f0)])
foo with Vector{Any}

```

(unrelated, but it’s very helpful to enclose your code in triple backticks ````` to make it more legible and ensure quotation marks are faithfully represented)