Bug#1061963: guix: Add comment in the README.Debian on the interest of the locally build guix binary generated by "guix pull"

[Grégory Mounié]

Package: guix
Version: 1.4.0-5
Severity: minor

Dear Maintainer,

By default, the /usr/bin/guix binary is always used. It is perfect for easy
bootstrapping. Nevertheless it is problematic for users that do not understand
guix behavior well. Any "guix pull" will start from the guix state at debian
build time, with, e.g., an outdated package list (at 2024-01-30: debian guix:
21K package, locally build guix: 28K package, debian guix: emacs 28.2, locally
build guix: emacs 29.1, ...) and long compilation.

Thus, after "guix pull" most users should used the newly build guix binary.
Nevertheless it is quite easy to ignore the related message and to not
understand why it is useful, or to mix it with the "guix install" messages.

I would had at the end of the README.Debian a small explanation. May be
something short like:

"""
Each user first "guix pull" command will build a new guix binary including the
current, at build time, dependence tree. Most user should probably use this new
guix binary thereafter. The "guix pull" command will display at its end the few
command lines that should be inserted in their bashrc/zshrc/... to change their
PATH.
Typically:
GUIX_PROFILE="/home/johndoe/.config/guix/current"
. "$GUIX_PROFILE/etc/profile"

The previous addition to the PATH is different and complementary to the end of
"guix install" command lines.
Typically:
GUIX_PROFILE="/home/johndoe/.guix-profile"
. "$GUIX_PROFILE/etc/profile"


-- System Information:
Debian Release: trixie/sid
APT prefers unstable
APT policy: (990, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 6.6.13-amd64 (SMP w/16 CPU threads; PREEMPT)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8), LANGUAGE=fr:en_US
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages guix depends on:
ii guile-3.0 3.0.8-2+b1
ii guile-3.0-libs 3.0.8-2+b1
ii guile-gcrypt 0.4.0-2
ii guile-git 0.5.2-5
ii guile-gnutls 4.0.0-1
ii guile-json 4.7.3-2
ii guile-lzlib 0.0.2-3
ii guile-sqlite3 0.1.3-3
ii guile-ssh 0.16.4-1
ii guile-zlib 0.1.0-4
ii libbz2-1.0 1.0.8-5+b2
ii libc6 2.37-14
ii libgcc-s1 14-20240127-1
ii libgcrypt20 1.10.3-2
ii libsqlite3-0 3.45.0-1
ii libssh-dev 0.10.6-2
ii libstdc++6 14-20240127-1
ii zlib1g 1:1.3.dfsg-3+b1

Versions of packages guix recommends:
ii ca-certificates 20230311
ii guile-avahi 0.4.1-2
ii less 590-2
pn nscd <none>
ii systemd 255.3-1

guix suggests no packages.

-- no debconf information