# Ref not change
**URL:** https://discourse.julialang.org/t/ref-not-change/33503
**Category:** New to Julia
**Tags:** question
**Created:** [January 17, 2020, 7:14pm UTC](https://discourse.julialang.org/t/ref-not-change/33503 "2020-01-17T19:14:39Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@andrey2185](https://discourse.julialang.org/u/andrey2185)
#### Post date: [January 17, 2020, 7:14pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/1 "2020-01-17T19:14:39Z")
Hello!
```julia
x = 10
ax = Ref(x)
x = 90
println(ax[]) # why 10 ?
```
---
### Author:  [@Mason](https://discourse.julialang.org/u/Mason)
#### Post date: [January 17, 2020, 7:35pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/2 "2020-01-17T19:35:55Z")
Here’s a step by step explanation of what your program does:
```julia
x = 10
```
This binds the value `10` to a variable `x`. Using `x` or the literal `10` should now be interchangeable.
```julia
ax = Ref(x)
```
This plops the **value** of `x` into a `Ref` and names that object `ax`. What you did is fully equivalent to `ax = Ref(10)`.
```julia
x = 90
```
This just rebinds the variable `x` to point to the value `90` instead of `10` for **future** uses. This rebinding is not retroactive.
```julia
println(ax[])
```
is then ‘equivalent’ to
```julia
println(Ref(10)[]
```
and
```julia
println(10)
```
---
### Author:  [@andrey2185](https://discourse.julialang.org/u/andrey2185)
#### Post date: [January 17, 2020, 7:47pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/3 "2020-01-17T19:47:57Z")
thank you
how to get value 90 from reference?
---
### Author:  [@Mason](https://discourse.julialang.org/u/Mason)
#### Post date: [January 17, 2020, 7:51pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/4 "2020-01-17T19:51:27Z")
Try this:
```julia
x = 10
ax = Ref(x)
ax[] = 90
println(ax[])
```
the line `ax[] = 90` says mutate the `Ref` so that it not stores `90` instead of `10`.
---
### Author:  [@andrey2185](https://discourse.julialang.org/u/andrey2185)
#### Post date: [January 17, 2020, 8:03pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/5 "2020-01-17T20:03:10Z")
but, how to get the correct value from ref when changing x ?
---
### Author:  [@pbayer](https://discourse.julialang.org/u/pbayer)
#### Post date: [January 17, 2020, 9:09pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/6 "2020-01-17T21:09:40Z")
why not taking a composite type? This is typesafe and needs no explicit pointers:
```julia
x = [10]
ax = x
x[1] = 90
ax[1]
```
`90`
or:
```julia
mutable struct mytype
y::Int
end
x = mytype(10)
ax = x
x.y = 90
ax.y
```
`90`
Why is this so? You could in your second assignment do `x = 90.0`. Then x would change to a `Float64` and ax would be in trouble. try like in C `int x 10`:
```julia
julia> x::Int = 10
ERROR: syntax: type declarations on global variables are not yet supported
....
```
---
### Author:  [@yuyichao](https://discourse.julialang.org/u/yuyichao)
#### Post date: [January 17, 2020, 9:14pm UTC](https://discourse.julialang.org/t/ref-not-change/33503/7 "2020-01-17T21:14:32Z")
It is strictly not allowed for assigning to a simple local variable to have such a effect so what you are asking for is impossible.