# Revising structs: please test the upcoming Revise

**URL:** https://discourse.julialang.org/t/revising-structs-please-test-the-upcoming-revise/132226
**Category:** Package Announcements
**Tags:** revise
**Created:** [September 9, 2025, 10:24am UTC](https://discourse.julialang.org/t/revising-structs-please-test-the-upcoming-revise/132226 "2025-09-09T10:24:57Z")
**Posts on this page:** 1
**Page:** 1

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### 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: [September 9, 2025, 10:24am UTC](https://discourse.julialang.org/t/revising-structs-please-test-the-upcoming-revise/132226/1 "2025-09-09T10:24:57Z")

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Now that [Julia 1.12-rc2 is out](https://discourse.julialang.org/t/julia-v1-12-0-rc2-is-now-available/132204), I’d like to ask willing volunteers to test it together with a branch of [Revise](https://github.com/timholy/Revise.jl) that supports redefining `struct`s and other constants. The core functionality needed to support this feature is only in Julia 1.12+, but most of the aspects that make this usable (e.g., recreating existing methods to support the new types, redefining dependent types that may wrap a redefined type) will be implemented in Revise. Only by widespread testing is this likely to be released in robust form.

Trying the new version is easy:

- `juliaup add beta` or whatever you need to do to install Julia 1.12-rc2
- `julia +beta -e 'using Pkg; Pkg.add(name="Revise"; rev="teh/struct_revision")'`
- Now do your normal work, but using `julia +beta` every time you launch Julia

If you want to go back to the released version at any point, you can use `pkg> free Revise`.

One important thing to keep in mind: if you change a `struct` definition, you will need to recreate any _data_ that involve that type. That is, if you’re working on code that accepts a `list` of `Foo` objects and you then redefine `Foo`, you will need to recreate `list` using the new `Foo` before you can pass it to any methods.

Please report any bugs to [Fix struct/const revision by timholy · Pull Request #894 · timholy/Revise.jl · GitHub](https://github.com/timholy/Revise.jl/pull/894)