Pandoc conversion

doc/manual/src/release-notes/rl-1.7.md

@@ -0,0 +1,140 @@
+# Release 1.7 (2014-04-11)
+
+In addition to the usual bug fixes, this release has the following new
+features:
+
+  - Antiquotation is now allowed inside of quoted attribute names (e.g.
+    `set."${foo}"`). In the case where the attribute name is just a
+    single antiquotation, the quotes can be dropped (e.g. the above
+    example can be written `set.${foo}`). If an attribute name inside of
+    a set declaration evaluates to `null` (e.g. `{ ${null} = false; }`),
+    then that attribute is not added to the set.
+
+  - Experimental support for cryptographically signed binary caches. See
+    [the commit for
+    details](https://github.com/NixOS/nix/commit/0fdf4da0e979f992db75cc17376e455ddc5a96d8).
+
+  - An experimental new substituter, `download-via-ssh`, that fetches
+    binaries from remote machines via SSH. Specifying the flags
+    `--option
+                    use-ssh-substituter true --option ssh-substituter-hosts
+                    user@hostname` will cause Nix to download binaries from the
+    specified machine, if it has them.
+
+  - `nix-store -r` and `nix-build` have a new flag, `--check`, that
+    builds a previously built derivation again, and prints an error
+    message if the output is not exactly the same. This helps to verify
+    whether a derivation is truly deterministic. For example:
+    
+        $ nix-build '<nixpkgs>' -A patchelf
+        …
+        $ nix-build '<nixpkgs>' -A patchelf --check
+        …
+        error: derivation `/nix/store/1ipvxs…-patchelf-0.6' may not be deterministic:
+          hash mismatch in output `/nix/store/4pc1dm…-patchelf-0.6.drv'
+
+  - The `nix-instantiate` flags `--eval-only` and `--parse-only` have
+    been renamed to `--eval` and `--parse`, respectively.
+
+  - `nix-instantiate`, `nix-build` and `nix-shell` now have a flag
+    `--expr` (or `-E`) that allows you to specify the expression to be
+    evaluated as a command line argument. For instance, `nix-instantiate
+    --eval -E
+                    '1 + 2'` will print `3`.
+
+  - `nix-shell` improvements:
+    
+      - It has a new flag, `--packages` (or `-p`), that sets up a build
+        environment containing the specified packages from Nixpkgs. For
+        example, the command
+        
+            $ nix-shell -p sqlite xorg.libX11 hello
+        
+        will start a shell in which the given packages are present.
+    
+      - It now uses `shell.nix` as the default expression, falling back
+        to `default.nix` if the former doesn’t exist. This makes it
+        convenient to have a `shell.nix` in your project to set up a
+        nice development environment.
+    
+      - It evaluates the derivation attribute `shellHook`, if set. Since
+        `stdenv` does not normally execute this hook, it allows you to
+        do `nix-shell`-specific setup.
+    
+      - It preserves the user’s timezone setting.
+
+  - In chroots, Nix now sets up a `/dev` containing only a minimal set
+    of devices (such as `/dev/null`). Note that it only does this if you
+    *don’t* have `/dev` listed in your `build-chroot-dirs` setting;
+    otherwise, it will bind-mount the `/dev` from outside the chroot.
+    
+    Similarly, if you don’t have `/dev/pts` listed in
+    `build-chroot-dirs`, Nix will mount a private `devpts` filesystem on
+    the chroot’s `/dev/pts`.
+
+  - New built-in function: `builtins.toJSON`, which returns a JSON
+    representation of a value.
+
+  - `nix-env -q` has a new flag `--json` to print a JSON representation
+    of the installed or available packages.
+
+  - `nix-env` now supports meta attributes with more complex values,
+    such as attribute sets.
+
+  - The `-A` flag now allows attribute names with dots in them, e.g.
+    
+        $ nix-instantiate --eval '<nixos>' -A 'config.systemd.units."nscd.service".text'
+
+  - The `--max-freed` option to `nix-store --gc` now accepts a unit
+    specifier. For example, `nix-store --gc --max-freed
+                    1G` will free up to 1 gigabyte of disk space.
+
+  - `nix-collect-garbage` has a new flag `--delete-older-than` N`d`,
+    which deletes all user environment generations older than N days.
+    Likewise, `nix-env
+                    --delete-generations` accepts a N`d` age limit.
+
+  - Nix now heuristically detects whether a build failure was due to a
+    disk-full condition. In that case, the build is not flagged as
+    “permanently failed”. This is mostly useful for Hydra, which needs
+    to distinguish between permanent and transient build failures.
+
+  - There is a new symbol `__curPos` that expands to an attribute set
+    containing its file name and line and column numbers, e.g. `{ file =
+    "foo.nix"; line = 10;
+                    column = 5; }`. There also is a new builtin function,
+    `unsafeGetAttrPos`, that returns the position of an attribute. This
+    is used by Nixpkgs to provide location information in error
+    messages, e.g.
+    
+        $ nix-build '<nixpkgs>' -A libreoffice --argstr system x86_64-darwin
+        error: the package ‘libreoffice-4.0.5.2’ in ‘.../applications/office/libreoffice/default.nix:263’
+          is not supported on ‘x86_64-darwin’
+
+  - The garbage collector is now more concurrent with other Nix
+    processes because it releases certain locks earlier.
+
+  - The binary tarball installer has been improved. You can now install
+    Nix by running:
+    
+        $ bash <(curl https://nixos.org/nix/install)
+
+  - More evaluation errors include position information. For instance,
+    selecting a missing attribute will print something like
+    
+        error: attribute `nixUnstabl' missing, at /etc/nixos/configurations/misc/eelco/mandark.nix:216:15
+
+  - The command `nix-setuid-helper` is gone.
+
+  - Nix no longer uses Automake, but instead has a non-recursive, GNU
+    Make-based build system.
+
+  - All installed libraries now have the prefix `libnix`. In particular,
+    this gets rid of `libutil`, which could clash with libraries with
+    the same name from other packages.
+
+  - Nix now requires a compiler that supports C++11.
+
+This release has contributions from Danny Wilson, Domen Kožar, Eelco
+Dolstra, Ian-Woo Kim, Ludovic Courtès, Maxim Ivanov, Petr Rockai,
+Ricardo M. Correia and Shea Levy.