# How to see list of available Package Versions? (AKA how to downgrade because Turing crashes?)

**URL:** <https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020>\
**Category:** General Usage\
**Tags:** package-manager, turing\
**Created:** [September 30, 2021, 11:18pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020 "2021-09-30T23:18:54Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![dlakelan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dlakelan/32/8491_2.png) [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Post date:** [September 30, 2021, 11:18pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/1 "2021-09-30T23:18:54Z")

</div>

I installed the latest Turing and now I can’t “using Turing” because:

```julia

julia> using Turing
ERROR: InitError: UndefVarError: Params not defined
Stacktrace:
  [1] top-level scope
    @ none:1
  [2] eval
    @ ./boot.jl:373 [inlined]
  [3] define_typeinf_code2()
    @ IRTools.Inner ~/.julia/packages/IRTools/BpoqK/src/reflection/reflection.jl:21
  [4] __init__ ()
    @ IRTools.Inner ~/.julia/packages/IRTools/BpoqK/src/IRTools.jl:37
  [5] _include_from_serialized(path::String, depmods::Vector{Any})
    @ Base ./loading.jl:768

```

This was working fine yesterday so I’d like to downgrade, but how do I find out what downgrade versions there are?

(BTW: I just guessed and did ] add Turing@0.8.1 and that now works, but I still want to know how to find out what versions are available).

---

<div class="post-metadata">

**Author:** ![jling](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jling/32/212909_2.png) [@jling](https://discourse.julialang.org/u/jling)\
**Post date:** [September 30, 2021, 11:31pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/2 "2021-09-30T23:31:38Z")

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[https://github.com/TuringLang/Turing.jl/releases](https://github.com/TuringLang/Turing.jl/releases)

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<div class="post-metadata">

**Author:** ![dlakelan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dlakelan/32/8491_2.png) [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Post date:** [September 30, 2021, 11:32pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/3 "2021-09-30T23:32:05Z")

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so there isn’t any Pkg command that lets you list em?

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<div class="post-metadata">

**Author:** ![jling](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jling/32/212909_2.png) [@jling](https://discourse.julialang.org/u/jling)\
**Post date:** [September 30, 2021, 11:32pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/4 "2021-09-30T23:32:21Z")

</div>

> [@dlakelan](#):
>
> Turing@0.8.1

that’s from 18 months ago…

---

<div class="post-metadata">

**Author:** ![dlakelan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dlakelan/32/8491_2.png) [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Post date:** [September 30, 2021, 11:32pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/5 "2021-09-30T23:32:50Z")

</div>

yeah, holy cow. Now I will have to see what the hell is holding it back!

---

<div class="post-metadata">

**Author:** ![dlakelan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dlakelan/32/8491_2.png) [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Post date:** [September 30, 2021, 11:46pm UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/6 "2021-09-30T23:46:14Z")

</div>

```julia
(@v1.7) pkg> add Turing@0.18.0
    Updating registry at `~/.julia/registries/General.toml`
   Resolving package versions...
ERROR: Unsatisfiable requirements detected for package Libtask [6f1fad26]:
 Libtask [6f1fad26] log:
 ├─possible versions are: 0.1.1-0.5.3 or uninstalled
 ├─restricted by compatibility requirements with Turing [fce5fe82] to versions: [0.4.0-0.4.2, 0.5.3]
 │ └─Turing [fce5fe82] log:
 │ ├─possible versions are: 0.5.0-0.18.0 or uninstalled
 │ └─restricted to versions 0.18.0 by an explicit requirement, leaving only versions 0.18.0
 ├─restricted by compatibility requirements with AdvancedPS [576499cb] to versions: 0.5.3
 │ └─AdvancedPS [576499cb] log:
 │ ├─possible versions are: 0.1.0-0.2.4 or uninstalled
 │ └─restricted by compatibility requirements with Turing [fce5fe82] to versions: 0.2.4
 │ └─Turing [fce5fe82] log: see above
 └─restricted by compatibility requirements with Libtask_jll [3ae2931a] to versions: 0.1.1-0.4.2 or uninstalled — no versions left
   └─Libtask_jll [3ae2931a] log:
     ├─possible versions are: 0.3.0-0.5.1 or uninstalled
     └─restricted by julia compatibility requirements to versions: [0.3.0-0.3.2, 0.5.0-0.5.1] or uninstalled

```

Seems like because I"m running Julia 1.7.0-beta3 that Libtask can’t hit 0.5.3 and hence Turing is held WAY back.

Installed Libtask#master and it updated Turing to 0.18.0 so I guess problem solved!

BUT: it still seems like it’d be good to have a Pkg command to list available versions?

---

<div class="post-metadata">

**Author:** ![GunnarFarneback](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gunnarfarneback/32/1827_2.png) [@GunnarFarneback](https://discourse.julialang.org/u/GunnarFarneback)\
**Post date:** [October 1, 2021, 6:05am UTC](https://discourse.julialang.org/t/how-to-see-list-of-available-package-versions-aka-how-to-downgrade-because-turing-crashes/69020/7 "2021-10-01T06:05:06Z")

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You probably don’t want to set any compat for your environment but you can use [PackageCompatUI](https://github.com/GunnarFarneback/PackageCompatUI.jl) to get a list of all releases and their registration dates:

```julia
(@v1.6) pkg> add PackageCompatUI
(@v1.6) pkg> activate --temp
(jl_k7HOZz) pkg> add Turing
julia> using PackageCompatUI
julia> compat_ui()
Save and quit: q, Help: ?
 > julia                                   
   Turing                                  

```

Move the cursor to `Turing` and hit return or right arrow:

```julia
Turing: 
 > [] 0.5.0 2018-09-19
   [] 0.5.1 2018-10-12
   [] 0.6.0 2018-12-10
   [] 0.6.1 2018-12-10
   [] 0.6.2 2018-12-14
   [] 0.6.4 2018-12-29
   [] 0.6.5 2019-01-19
   [] 0.6.6 2019-01-24
   [] 0.6.7 2019-02-04
   [] 0.6.8 2019-02-07
   [] 0.6.9 2019-02-18
   [] 0.6.11 2019-03-05
   [] 0.6.12 2019-03-12
   [] 0.6.13 2019-03-20
   [] 0.6.14 2019-03-29
   [] 0.6.15 2019-04-17
   [] 0.6.17 2019-04-25
   [] 0.6.18 2019-07-06
   [] 0.6.19 2019-07-24
v [] 0.6.21 2019-07-24

```

Navigate with up and down arrows to see the release history. Hit ‘q’ to leave without setting any compat.