Hi,

"guix package -i jupyter" fails with the following error:

guix package: error: profile contains conflicting entries for python-jupyter-console
package: error:   first entry: python-jupyter-console@5.0.0 /gnu/store/f0hzkjw58ys9qm2hf209vfdnbmm24zan-python-jupyter-console-5.0.0
guix package: error:    ... propagated from jupyter@1.0.0
guix package: error:   second entry: python-jupyter-console@5.0.0 /gnu/store/315alfzrhisyrkh6mhz4a1y8gj1ljxlr-python-jupyter-console-5.0.0
guix package: error:    ... propagated from python-ipython@5.3.0
guix package: error:    ... propagated from python-notebook@4.2.3
guix package: error:    ... propagated from jupyter@1.0.0
hint: You cannot have two different versions or variants of `jupyter' in the same profile.

As I dont have two different versions of jupyter I think it is due to the fact that two different "python-jupyter-console" packages exist in /gnu/packages/python.scm.

In the source code it states, because of a cyclic dependencies "python-jupyter-console" they strip it into a "minimal" version and use that
("python-jupyter-console"
;; The python-ipython and python-jupyter-console require each
;; other. To get the functionality in both packages working, strip
;; down the python-jupyter-console package when using it as an input
;; to python-ipython.
,python-jupyter-console-minimal)

in line 4409 of /gnu/packages/python.scm

So there indeed are two "python-jupyter-console" packages that collide.

If I run "guix environment --ad-hoc jupyter" the command succeeds, and jupyter works.

On the IRC lfam said that this was because these collisions were explicitly allowed in "guix environment"

Merry Christmas,
johannes