bug#28223: Guix documentation uses wrong install command

[Rosebud Uplink]

Package: guix

Version: 0.13.0

In the Guix documentation, category 2.1 (Binary Installation), step 3, the command used to augment the PATH doesn't give the wanted result.

3. Make root’s profile available under ~/.guix-profile:
[...]

# GUIX_PROFILE=$HOME/.guix-profile \
  source $GUIX_PROFILE/etc/profile

$GUIX_PROFILE is expanded first, and the "source" command will always be expanded as:

source /etc/profile

Putting a semicolon between the variable definition and the "source" command resolves this problem and has the required effect. 

# GUIX_PROFILE=$HOME/.guix-profile ; source $GUIX_PROFILE/etc/profile

The command could also be simplified by removing the definition of GUIX_PROFILE, and passing $HOME/.guix-profile/etc/profile to source.

System: Linux 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u2 (2017-06-26) x86_64 GNU/Linux

Libc: 2.19-18+deb8u10