# Indexing operation results in \`::ANY\` using \`code\_warntype\`

**URL:** <https://discourse.julialang.org/t/indexing-operation-results-in-any-using-code-warntype/5145>\
**Category:** General Usage\
**Created:** [July 31, 2017, 1:43am UTC](https://discourse.julialang.org/t/indexing-operation-results-in-any-using-code-warntype/5145 "2017-07-31T01:43:14Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![stillyslalom](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/stillyslalom/32/45687_2.png) [@stillyslalom](https://discourse.julialang.org/u/stillyslalom)\
**Post date:** [July 31, 2017, 1:43am UTC](https://discourse.julialang.org/t/indexing-operation-results-in-any-using-code-warntype/5145/1 "2017-07-31T01:43:14Z")

</div>

MWE on Julia 0.6, OSX x64 binary release; let me know if I should file a bug report. Seems as if the type of `u0` should be easy to infer.

```julia
init(f, x) = f.(x)
function test(f, nx)
    x = linspace(0., 1., nx)
    u = init(f, x)
    u0 = u[1:nx-1]::Array{Float64, 1}
    return u0
end
@code_warntype test(sin, 10)

```

results in

```julia
Variables:
  #self#::#test
  f::Base.#sin
  nx::Int64
  x::StepRangeLen{Float64,Base.TwicePrecision{Float64},Base.TwicePrecision{Float64}}
  u::Array{Float64,1}
  u0::ANY
etc.

```

(full `@code_warntype` output [here](https://gist.github.com/anonymous/956058e86319b398e286a36f4805a4a7#file-code_warntype-output))

---

<div class="post-metadata">

**Author:** ![yuyichao](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/yuyichao/32/20_2.png) [@yuyichao](https://discourse.julialang.org/u/yuyichao)\
**Post date:** [July 31, 2017, 1:53am UTC](https://discourse.julialang.org/t/indexing-operation-results-in-any-using-code-warntype/5145/2 "2017-07-31T01:53:43Z")

</div>

Harmless unused variable. Ignore it if you didn’t see it in the code.