Bug#510161: apt_preferences vs. sources.list

[jidanni@jidanni.org]

Package: apt
Version: 0.7.19+b1
Severity: wishlist
File: /usr/share/man/man5/apt_preferences.5.gz

We read

       Several instances of the same version of a package may be available when the sources.list(5) file contains
       references to more than one source. In this case apt-get downloads the instance listed earliest in the
       sources.list(5) file. The APT preferences file does not affect the choice of instance, only the choice of
       version.

All I know is here's my order,
deb http://ftp.tw.debian.org/debian experimental main contrib non-free
deb http://ftp.tw.debian.org/debian unstable main contrib non-free

But that's not enough to change the order of what will be installed:
$ set bless
$ apt-cache policy $@
bless:
  Installed: (none)
  Candidate: 0.5.2-1.2
  Version table:
     0.5.2-2 0
          1 http://ftp.tw.debian.org experimental/main Packages
     0.5.2-1.2 0
        500 http://ftp.tw.debian.org unstable/main Packages

One needs to set a variable:
$ apt-cache -o APT::Default-Release=experimental policy $@
bless:
  Installed: (none)
  Candidate: 0.5.2-2
  Version table:
     0.5.2-2 0
        990 http://ftp.tw.debian.org experimental/main Packages
     0.5.2-1.2 0
        500 http://ftp.tw.debian.org unstable/main Packages


Therefore that paragraph needs some examples to clarify what it is
talking about.

Also no priority "1" is mentioned on apt_preferences(5).