Fixing version of mathlib4

Stream: mathlib4

[Alexan Ayrapetyan]

Hi. Is there a way to install not the latest but the most stable version of mathlib4 and lea4? So for instance I'd like to get 4.12.0

Does the lean4 4.12.0 or any other version correspond to the same version of mathlib4 tag?

[Jon Eugster]

You want to specify v4.12.0 in the lean-toolchain file and then in your project's "lakefile" you can specify the version of mathlib you are requiring to be v4.12.0

Im on mobile rn so can't copy-paste the exact code, but if you get stuck, you could provide the content of these two files here to get you fixed.

There's also this docs PR of mine which has a section "following stable versions of dependencies" which contains instruction how to set up your project correctly to the best of my knowledge/experience.

[Alexan Ayrapetyan]

Tank you, this helped a lot!