* doc/guix.texi (Setuid Programs): Fix typos.

Suggested by Malcolm Cook <MEC@stowers.org>.

* doc/guix.texi (Binary Installation): Suggest --warning=no-timestamp.

Fixes <http://bugs.gnu.org/21111>.
Reported by Dave Love <fx@gnu.org>.

* doc/guix.texi (Binary Installation): Add paragraph about "implausibly old
  time stamps" warning from tar.

* guix/scripts/size.scm (show-help, %options): Add --substitute-urls.
  (%default-options): Add 'substitute-urls'.
  (guix-size): Honor it.
* doc/guix.texi (Invoking guix size): Document it.

Suggested by remo_ on IRC.

* doc/guix.texi (System Installation): Explicitly mention user account
  passwords.
  (User Accounts): Add 'user-account-password' anchor.

* doc/guix.texi (GNU Distribution): Use the new package list URL.
  (Limitations): Mention Enlightenment and improve wording.  Update the
  package count.

* guix/build-system/ruby.scm (build): add 'gem-flags' key
* guix/build/ruby-build-system.scm (build): use 'gem-flags' key
* doc/guix.texi (Build Systems): Mention #:gem-flags.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

* gnu/system/file-systems.scm (<file-system>)[dependencies]: New field.
* gnu/system.scm (other-file-system-services)[requirements]: Honor
  'file-system-dependencies'.
* doc/guix.texi (File Systems): Document it.

* gnu/system.scm (<operating-system>)[kernel-arguments]: New field.
  (operating-system-grub.cfg): Honor it.
  (operating-system-parameters-file): Add 'kernel-arguments' to the parameters
  file.
* guix/scripts/system.scm (previous-grub-entries)[system->grub-entry]: Read
  the 'kernel-arguments' field of the parameters file, when available.
* gnu/system/vm.scm (system-qemu-image/shared-store-script):
  Use (operating-system-kernel-arguments os) in '-append'.
* doc/guix.texi (operating-system Reference): Document it.

* etc/guix-daemon.service.in: New file, provided by Ricardo Wurmus.
* daemon.am (CLEANFILES): Add etc/guix-daemon.service.
  (systemdservicedir, nodist_systemdservice_DATA): New variables.
  (EXTRA_DIST): Add etc/guix-daemon.service.in.
* doc/guix.texi (Binary Installation, Build Environment Setup): Mention
  'guix-daemon.service'.

* doc/guix.texi (Binary Installation): Reinstate bit about creating group and
  user accounts, which was inadvertently removed in 01dbc7e0.

Fixes <http://bugs.gnu.org/19778>.
Reported by Mark H Weaver <mhw@netris.org>.

* gnu/system/file-systems.scm (%uuid-rx): New variable.
  (string->uuid): New procedure.
  (uuid): New macro.
* tests/file-systems.scm: New file.
* Makefile.am (SCM_TESTS): Add it.
* doc/guix.texi (File Systems): Give an example of UUID.

* guix/scripts/build.scm (%standard-build-options,
  show-build-options-help): Add --substitute-urls=URLS.
  (set-build-options-from-command-line): Honor it.
* guix/store.scm (%default-substitute-urls): Make public.
* doc/guix.texi (Substitutes): Add xref to the client --substitute-urls
  option.
  (Invoking guix build): Document it.
  (Invoking guix-daemon): Add 'daemon-substitute-urls' anchor.

* gnu/packages/gcc.scm (gcc-configure-flags-for-triplet): On armhf,
  include --with-fpu=neon.
* doc/guix.texi (GNU Distribution): Document that our armhf port
  requires NEON.

* doc/guix.texi (Daemon Offload Setup): Mention that we're using lsh.  Mention
  GUILE_LOAD_PATH settings on the target machine.  Explain that machines must
  authorize each other.

* doc/guix.texi (Invoking guix import): Remove extraneous quotes around URLs.

* Makefile.am (MODULES): Add 'guix/build-system/emacs.scm' and
  'guix/build/emacs-build-system.scm'.
* guix/build-system/emacs.scm: New file.
* guix/build/emacs-build-system.scm: New file.
* doc/guix.texi (Build Systems): Document it.

* guix/import/elpa.scm: New file.
* guix/scripts/import.scm: Add "elpa" to 'importers'.
* guix/scripts/import/elpa.scm: New file.
* Makefile.am (MODULES): Add 'guix/import/elpa.scm' and
  'guix/scripts/import/elpa.scm'.
  (SCM_TESTS): Add 'tests/elpa.scm'.
* doc/guix.texi (Invoking guix import): Document it.
* tests/elpa.scm: New file.
* po/guix/POTFILES.in: Add 'guix/scripts/import/elpa.scm'.

Fixes <http://bugs.gnu.org/18747>.

* guix/derivations.scm (substitutable-derivation?): Rewrite to check for
  "allowSubstitutes".
  (derivation): Add #:substitutable? parameter.
  [user+system-env-vars]: Honor it.
  (build-expression->derivation): Add #:substitutable? and honor it.
* guix/gexp.scm (gexp->derivation): Likewise.
* tests/derivations.scm ("derivation-prerequisites-to-build and substitutes,
  non-substitutable build"): Use #:substitutable? instead of #:local-build?.
  ("substitutable-derivation?", "derivation-prerequisites-to-build and
  substitutes, local build"): New tests.
* guix/download.scm (url-fetch): Adjust comment.
* guix/git-download.scm (git-fetch): Likewise.
* guix/build-system/gnu.scm (gnu-build, gnu-cross-build): Use #:substitutable?
  instead of #:local-build?.
* doc/guix.texi (Derivations, G-Expressions): Adjust accordingly.

* guix/scripts/environment.scm (create-environment): Define 'GUIX_ENVIRONMENT'.
* doc/guix.texi (Invoking guix environment): Document it.
* gnu/system/shadow.scm (default-skeletons): Adjust 'PS1' depending on whether
  'GUIX_ENVIRONMENT' is defined.

* doc/guix.texi (Invoking guix environment): Add footnote about .bashrc
  vs. .bash_profile.

* guix/scripts/environment.scm (package+propagated-inputs): Add 'output'
  parameter.  Use it in return value.
  (options/resolve-packages): Use 'append-map' instead of 'map'.  For 'load'
  and 'expression', return all the outputs of the resulting package.  For
  'package', use 'specification->package+output' instead of
  'specification->package'.
  (guix-environment): Adjust uses of PACKAGES accordingly.
* doc/guix.texi (Invoking guix environment): Document it.
* tests/guix-environment.sh: Add test for --ad-hoc guile-bootstrap:out.

* guix/scripts/environment.scm (show-help, %options): Add -s/--system.
  (%default-options): Add 'system' pair.
  (guix-environment): Pass 'system' value from OPTS to 'lower-inputs'.
* doc/guix.texi (Invoking guix environment): Document it.

* doc/environment-gdb.scm: New file.
* doc.am (EXTRA_DIST): Add it.
* doc/guix.texi (Invoking guix environment): Clarify wording of the first
  example.  Add a --ad-hoc example upfront.  Add an example for '-e', and one
  for '-l'.

* doc/guix.texi (The Store Monad): Add funny quote about "running" a monadic
  value.

* doc/guix.texi (Application Setup): New node.

* emacs/guix-base.el (guix-edit-package): New function.
* emacs/guix-list.el (guix-list-edit-package): New command.  Bind it to
  "e" key.
* emacs/guix-main.scm (package-location-string): New procedure.
* doc/emacs.texi (Emacs List buffer): Document "e" key binding.
* doc/guix.texi (Invoking guix edit): Mention "package list" buffer.

* guix/scripts/size.scm (profile->page-map): New procedures.
  (show-help, %options):  Add --map-file.
  (guix-size): Honor it.
* doc/guix.texi (Invoking guix size): Document it.
* doc/images/coreutils-size-map.png: New file.
* doc.am (dist_infoimage_DATA): Add it.

* guix/scripts/size.scm: New file.
* Makefile.am (MODULES): Add it.
  (SCM_TESTS): Add tests/size.scm.
* doc.am (SUBCOMMANDS): Add 'size'.
* po/guix/POTFILES.in: Add guix/scripts/size.scm.
* tests/size.scm: New file.
* doc/guix.texi (Packages with Multiple Outputs): Add xref to "Invoking guix
  size".
  (Invoking guix size): New node.
  (Invoking guix gc): Add index for "closure" and xref to the above.
* doc/contributing.texi (Submitting Patches): Use @enumerate for the check
  list.  Add item about 'guix size'.

* guix/scripts/edit.scm: New file.
* Makefile.am (MODULES): Add it.
* doc.am (SUBCOMMANDS): Add 'edit'.
* doc/guix.texi (Defining Packages): Add xref to "Invoking guix edit".
  (Invoking guix edit): New node.
* po/guix/POTFILES.in: Add it.

* gnu/system.scm (<operating-system>): Rename record field.
  (etc-directory): Rename argument.
  (operating-system-etc-directory): Adjust accordingly.
* doc/guix.texi (operating-system Reference): Likewise.

Suggested by Mark H Weaver and others
at <http://lists.gnu.org/archive/html/guix-devel/2015-06/msg00227.html>.

* gnu/services/desktop.scm (%desktop-services): Remove call to 'lsh-service'.
* doc/guix.texi (Desktop Services): Adjust accordingly.

* HACKING (Contributing): New section.
  (Building from Git, The Perfect Setup, Coding Style, Submitting Patches):
  Move to ...
* doc/guix.texi (Running Guix Before It Is Installed): Likewise.
* doc/contributing.texi: ... here. New file.
* doc.am (EXTRA_DIST): Use it.
* README (Installation): Adapt to it.
* configure.ac (DOT): Likewise.

* guix/scripts/build.scm (package-with-source)[tarball-base-name]: Gracefully
  handle file names that lack an extension.
  Pass #:recursive? #t to 'download-to-store'.
* guix/download.scm (download-to-store): Add #:recursive? parameter and pass
  it to 'add-to-store'.
* doc/guix.texi (Invoking guix build): Add an example of --with-source with a
  directory.

* guix/import/cabal.scm: New file.
* guix/import/hackage.scm: Update to use the new Cabal parsing module.
* tests/hackage.scm: Update tests.
* guix/scripts/import/hackage.scm: Add new '--cabal-environment' and '--stdin'
  options.
* doc/guix.texi: ... and document them.
* Makefile.am (MODULES): Add 'guix/import/cabal.scm',
  'guix/import/hackage.scm' and 'guix/scripts/import/hackage.scm'.
  (SCM_TESTS): Add 'tests/hackage.scm'.

Suggested by Thomas Schwinge <thomas@codesourcery.com> and others.

* doc/guix.texi (Binary Installation): Suggest unpacking in /tmp rather than /.

Suggested by Thomas Schwinge <thomas@codesourcery.com>.

* gnu/system/install.scm (self-contained-tarball): Remove
  "/root/.guix-profile" from the 'tar' arguments.
* doc/guix.texi (Binary Installation): Add a step to create
  ~root/.guix-profile.

Suggested by Federico Beffa <beffa@fbengineering.ch>.

* guix/monads.scm (bind-syntax): New macro.
  (with-monad): Use it instead of 'identifier-syntax'.
* tests/monads.scm (">>= with more than two arguments"): New test.
* doc/guix.texi (The Store Monad): Explain that there can be several MPROC.
  Add an example.

Suggested by Thomas Schwinge <thomas@codesourcery.com>.

* doc/guix.texi (Build Environment Setup): Explain where the number of build
  users comes from.

* guix/scripts/gc.scm (show-help, %options): Add --verify.
  (guix-gc): Handle it.
* doc/guix.texi (Invoking guix gc): Document --verify, and move --optimize
  description right below it.