# How define this Dict more precise?
**URL:** https://discourse.julialang.org/t/how-define-this-dict-more-precise/43807
**Category:** New to Julia
**Created:** [July 28, 2020, 9:40am UTC](https://discourse.julialang.org/t/how-define-this-dict-more-precise/43807 "2020-07-28T09:40:08Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@Darione](https://discourse.julialang.org/u/Darione)
#### Post date: [July 28, 2020, 9:40am UTC](https://discourse.julialang.org/t/how-define-this-dict-more-precise/43807/1 "2020-07-28T09:40:08Z")
I can’t understand why … :-/
What is wrong in defining a dictionary in a more precise way?
```julia
julia> x = Dict()
Dict{Any,Any} with 0 entries
julia> x["weight"]=105
105
julia> x["number"]=3
3
julia> x
Dict{Any,Any} with 2 entries:
"weight" => 105
"number" => 3
julia> y = Dict{String,Int64}
Dict{String,Int64}
julia> y["weight"]=105
ERROR: MethodError: no method matching setindex!(::Type{Dict{String,Int64}}, ::Int64, ::String)
Stacktrace:
[1] top-level scope at REPL[55]:1
julia>
```
---
### Author:  [@paulmelis](https://discourse.julialang.org/u/paulmelis)
#### Post date: [July 28, 2020, 9:50am UTC](https://discourse.julialang.org/t/how-define-this-dict-more-precise/43807/2 "2020-07-28T09:50:27Z")
> [@Darione](#):
>
> `julia> y = Dict{String,Int64}`
This doesn’t create a dict, but assigns the type to `y`. Instead, use `y = Dict{String,Int64}()`
---
### Author:  [@Darione](https://discourse.julialang.org/u/Darione)
#### Post date: [July 28, 2020, 10:56am UTC](https://discourse.julialang.org/t/how-define-this-dict-more-precise/43807/3 "2020-07-28T10:56:23Z")
Ah, thank you very much.
Dario