# Why effect inference fails?

**URL:** https://discourse.julialang.org/t/why-effect-inference-fails/92293
**Category:** General Usage
**Created:** [December 29, 2022, 9:23pm UTC](https://discourse.julialang.org/t/why-effect-inference-fails/92293 "2022-12-29T21:23:03Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![jar1](https://avatars.discourse-cdn.com/v4/letter/j/c0e974/32.png) [@jar1](https://discourse.julialang.org/u/jar1)
#### Post date: [December 29, 2022, 9:23pm UTC](https://discourse.julialang.org/t/why-effect-inference-fails/92293/1 "2022-12-29T21:23:03Z")

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Why is it unsure about `nothrow`?

```julia
julia> f(x) = x * x
f (generic function with 1 method)

julia> Base.infer_effects(*, (Int, Int))
(+c,+e,+n,+t)

julia> Base.infer_effects(f, (Int, Int))
(+c,+e,?n,+t)

julia> versioninfo()
Julia Version 1.8.1
Commit afb6c60d69a (2022-09-06 15:09 UTC)
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 24 × AMD Ryzen 9 3900XT 12-Core Processor
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-13.0.1 (ORCJIT, znver2)
  Threads: 1 on 24 virtual cores
Environment:
  LD_LIBRARY_PATH = 

```

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<div class="post-metadata">

### Author: ![giordano](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/giordano/32/2166_2.png) [@giordano](https://discourse.julialang.org/u/giordano)
#### Post date: [December 29, 2022, 9:37pm UTC](https://discourse.julialang.org/t/why-effect-inference-fails/92293/2 "2022-12-29T21:37:58Z")

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Probably because you got signature wrong, your `f` takes a single argument, not two.