# An empty array as the default value for optional arguments
**URL:** https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068
**Category:** New to Julia
**Created:** [November 1, 2018, 8:02pm UTC](https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068 "2018-11-01T20:02:56Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@chkwon](https://discourse.julialang.org/u/chkwon)
#### Post date: [November 1, 2018, 8:02pm UTC](https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068/1 "2018-11-01T20:02:56Z")
```julia
function foo(x::Int64, y::Array{String}=Array{String}(undef,0))
return x + length(y)
end
```
When `y` is an optional argument, I want to assign an empty array as the default value. While the above code works, it doesn’t seem easy to read (and not pretty). Is there a more desirable way of doing this?
---
### Author:  [@fredrikekre](https://discourse.julialang.org/u/fredrikekre)
#### Post date: [November 1, 2018, 8:13pm UTC](https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068/2 "2018-11-01T20:13:01Z")
```julia
function foo(x::Int64, y::Array{String}=String[])
return x + length(y)
end
```
---
### Author:  [@yuyichao](https://discourse.julialang.org/u/yuyichao)
#### Post date: [November 1, 2018, 8:14pm UTC](https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068/3 "2018-11-01T20:14:09Z")
There’s no special syntax for “empty array as default value”. You can use `String[]` to create an empty array though, and you don’t necessarily need the `::Array{String}` (it seems that you more likely want `Vector{String}` at least) and you almost certainly don’t need/want the `Int64`.
---
### Author:  [@chkwon](https://discourse.julialang.org/u/chkwon)
#### Post date: [November 1, 2018, 11:52pm UTC](https://discourse.julialang.org/t/an-empty-array-as-the-default-value-for-optional-arguments/17068/4 "2018-11-01T23:52:54Z")
Thanks. The function return value was just arbitrarily created. In fact `x` needs to be an integer since it will be used as an index for an array. But I guess it needs better be `Integer` instead of `Int64`. For the array part in my case, I think you are right. I don’t need to specify the type for `y` I guess.