# Defining a new function produces a warning in Revise (1.12)

**URL:** <https://discourse.julialang.org/t/defining-a-new-function-produces-a-warning-in-revise-1-12/133635>\
**Category:** General Usage\
**Tags:** revise\
**Created:** [November 4, 2025, 7:58am UTC](https://discourse.julialang.org/t/defining-a-new-function-produces-a-warning-in-revise-1-12/133635 "2025-11-04T07:58:39Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![phma](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/phma/32/6576_2.png) [@phma](https://discourse.julialang.org/u/phma)\
**Post date:** [November 4, 2025, 7:58am UTC](https://discourse.julialang.org/t/defining-a-new-function-produces-a-warning-in-revise-1-12/133635/1 "2025-11-04T07:58:39Z")

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I recently upgraded from Julia 1.11 to 1.12.1. I’m writing a program and have `Revise` in `startup.jl`. I write a new function `permcode`, export it, and call it to test if it works right. I get this warning:

```julia-auto
julia> permcode(Codeword([2,3,5,4,3,1])
       )
WARNING: Detected access to binding `MumzelCode.permcode` in a world prior to its definition world.
  Julia 1.12 has introduced more strict world age semantics for global bindings.
  !!! This code may malfunction under Revise.
  !!! This code will error in future versions of Julia.
Hint: Add an appropriate `invokelatest` around the access to this binding.
To make this warning an error, and hence obtain a stack trace, use `julia --depwarn=error`.
436

```

I exit and restart Julia, defeating the purpose of `Revise`, and try again:

```julia-auto
julia> permcode(Codeword([2,3,5,4,3,1]))
436

```

Same answer, which is correct. I’m not using `eval` or including something at runtime, so why am I getting this warning, and how can I avoid getting it?

---

<div class="post-metadata">

**Author:** ![tim.holy](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tim.holy/32/52_2.png) [@tim.holy](https://discourse.julialang.org/u/tim.holy)\
**Post date:** [November 4, 2025, 10:17am UTC](https://discourse.julialang.org/t/defining-a-new-function-produces-a-warning-in-revise-1-12/133635/2 "2025-11-04T10:17:29Z")

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Revise is still being updated for 1.12. For the moment you can ignore this warning.