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3308 commits

Author SHA1 Message Date
Shea Levy 18fefacf7d Dynamic attrs
This adds new syntax for attribute names:

* attrs."${name}" => getAttr name attrs
* attrs ? "${name}" => isAttrs attrs && hasAttr attrs name
* attrs."${name}" or def => if attrs ? "${name}" then attrs."${name}" else def
* { "${name}" = value; } => listToAttrs [{ inherit name value; }]

Of course, it's a bit more complicated than that. The attribute chains
can be arbitrarily long and contain combinations of static and dynamic
parts (e.g. attrs."${foo}".bar."${baz}" or qux), which is relatively
straightforward for the getAttrs/hasAttrs cases but is more complex for
the listToAttrs case due to rules about duplicate attribute definitions.

For attribute sets with dynamic attribute names, duplicate static
attributes are detected at parse time while duplicate dynamic attributes
are detected when the attribute set is forced. So, for example, { a =
null; a.b = null; "${"c"}" = true; } will be a parse-time error, while
{ a = {}; "${"a"}".b = null; c = true; } will be an eval-time error
(technically that case could theoretically be detected at parse time,
but the general case would require full evaluation). Moreover, duplicate
dynamic attributes are not allowed even in cases where they would be
with static attributes ({ a.b.d = true; a.b.c = false; } is legal, but {
a."${"b"}".d = true; a."${"b"}".c = false; } is not). This restriction
might be relaxed in the future in cases where the static variant would
not be an error, but it is not obvious that that is desirable.

Finally, recursive attribute sets with dynamic attributes have the
static attributes in scope but not the dynamic ones. So rec { a = true;
"${"b"}" = a; } is equivalent to { a = true; b = true; } but rec {
"${"a"}" = true; b = a; } would be an error or use a from the
surrounding scope if it exists.

Note that the getAttr, getAttr or default, and hasAttr are all
implemented purely in the parser as syntactic sugar, while attribute
sets with dynamic attribute names required changes to the AST to be
implemented cleanly.

This is an alternative solution to and closes #167

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-31 20:59:49 +00:00
Shea Levy 136f2f7046 Add the ExprBuiltin Expr type to the AST
Certain desugaring schemes may require the parser to use some builtin
function to do some of the work (e.g. currently `throw` is used to
lazily cause an error if a `<>`-style path is not in the search path)
Unfortunately, these names are not reserved keywords, so an expression
that uses such a syntactic sugar will not see the expected behavior
(see tests/lang/eval-okay-redefine-builtin.nix for an example).

This adds the ExprBuiltin AST type, which when evaluated uses the value
from the rootmost variable scope (which of course is initialized
internally and can't shadow any of the builtins).

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-31 17:45:47 +00:00
Shea Levy 5ba5993470 nix-shell --pure: Don't clear IN_NIX_SHELL
Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-30 16:59:24 +01:00
Eelco Dolstra b352fe2775 Revert "Scan /proc/<pid>/cmdline for GC roots"
This reverts commit 194e3374b8.
Checking the command line for GC roots means that

  $ nix-store --delete $path

will fail because $path is now a root because it's mentioned on the
command line.
2013-12-20 14:18:24 +01:00
Eelco Dolstra 8931bf7168 Doh 2013-12-20 13:09:12 +00:00
Petr Rockai f1e5dedb61 perl: Call loadConfFile() in doInit to avoid screwing sqlite journal mode.
If the database is opened through perl bindings (and even though nix.conf has
use-sqlite-wal set to false), the database is automatically converted into WAL
mode. This makes the next nix process to access the database convert it back to
"truncate". If the database is still open at the time in wal mode by the perl
program, this fails and crashes the nix doing the wal -> truncate conversion.
2013-12-20 13:59:52 +01:00
Eelco Dolstra 7d203faff6 nix-env --set-flag: Barf if a selector doesn't match any installed package
Fixes #184.
2013-12-20 13:56:42 +01:00
Eelco Dolstra 194e3374b8 Scan /proc/<pid>/cmdline for GC roots 2013-12-20 13:31:31 +01:00
Eelco Dolstra 769f662165 nix-shell: Don't warn about the lack of a GC root 2013-12-20 12:19:10 +00:00
Eelco Dolstra 0c1198cf08 nix-shell: Set $IN_NIX_SHELL before evaluation
This has some hacky applications.
2013-12-20 13:11:41 +01:00
Eelco Dolstra 65a6452240 nix-shell: Handle --option correctly
Fixes #181.
2013-12-20 13:10:14 +01:00
Eelco Dolstra 7b0d8fb23d nix-shell --pure: Keep $TERM 2013-12-17 18:16:04 +01:00
Shea Levy e36229d27f Bump language version for new storePath feature
This will allow e.g. channel expressions to use builtins.storePath IFF
it is safe to do so without knowing if the path is valid yet.

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-10 15:07:04 +01:00
Shea Levy 22d665019a builtins.storePath: Try to substitute the path if it is not yet valid
Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-10 15:07:04 +01:00
Eelco Dolstra a6add93d73 Garbage collector: Release locks on temporary root files
This allows processes waiting for such locks to proceed during the
trash deletion phase of the garbage collector.
2013-12-10 13:13:59 +01:00
Eelco Dolstra c5b8fe3151 Print a trace message if a build fails due to the platform being unknown 2013-12-05 14:31:57 -05:00
Eelco Dolstra 709cbe4e76 Include <cstring> for memset
This should fix building on Illumos.
2013-11-22 10:00:43 +00:00
Eelco Dolstra d4a76ff0e4 Bump version number 2013-11-19 14:45:19 +01:00
Eelco Dolstra 30b986908e Check meta values and warn about bad ones 2013-11-19 14:29:39 +01:00
Eelco Dolstra 0f24400d90 Generalise meta attributes 2013-11-19 14:09:14 +01:00
Eelco Dolstra 990126cde0 Shorter error message 2013-11-19 14:09:14 +01:00
Eelco Dolstra af94a70ba6 Drop support for user environment manifests in ATerm format 2013-11-19 14:09:14 +01:00
Eelco Dolstra 245e26408f nix-env -q: Add a --json flag 2013-11-19 00:41:45 +01:00
Eelco Dolstra 5fea98111b Refactor JSON output 2013-11-19 00:33:06 +01:00
Eelco Dolstra 77c13cdf56 Add a toJSON primop 2013-11-19 00:04:11 +01:00
Eelco Dolstra 285df765b9 Add a primop unsafeGetAttrPos to return the position of an attribute 2013-11-18 22:22:35 +01:00
Eelco Dolstra fc33fd86b7 Add a symbol __curPos that expands to the current source location
I.e. an attribute set { file = <string>; line = <int>; column = <int>; }.
2013-11-18 20:16:02 +01:00
Eelco Dolstra 90b5e69284 Support quoted attribute names in -A
This is requires if you have attribute names with dots in them.  So
you can now say:

  $ nix-instantiate '<nixos>' -A 'config.systemd.units."postgresql.service".text' --eval-only

Fixes #151.
2013-11-18 10:21:12 +00:00
Eelco Dolstra a478e8a7bb Remove nix-setuid-helper
AFAIK, nobody uses it, it's not maintained, and it has no tests.
2013-11-14 11:57:37 +01:00
Eelco Dolstra 89e6781cc5 Make function calls show up in stack traces again
Note that adding --show-trace prevents functions calls from being
tail-recursive, so an expression that evaluates without --show-trace
may fail with a stack overflow if --show-trace is given.
2013-11-12 12:51:59 +01:00
Eelco Dolstra 2bcb384e95 Add a test to check that tail calls run in bounded stack space 2013-11-12 12:34:22 +01:00
Eelco Dolstra c897bac549 Make function calls tail-recursive 2013-11-12 11:32:23 +00:00
Eelco Dolstra 273322c773 Make ifs and asserts tail-recursive
The local Value object prevented g++ from making a tail call.  Not
clear why.  In any case, not using a temporary makes g++ do the tail
call.
2013-11-12 11:32:23 +00:00
Eelco Dolstra 4badd7ed17 Get rid of an intermediary on the stack 2013-11-12 11:32:23 +00:00
Eelco Dolstra 8d6418d46e Fix building without a garbage collector
http://hydra.nixos.org/build/6695350
2013-10-28 22:51:12 +01:00
Eelco Dolstra dec2f19502 Fix a segfault in genericClosure
It kept temporary data in STL containers that were not scanned by
Boehm GC, so Nix programs using genericClosure could randomly crash if
the garbage collector kicked in at a bad time.

Also make it a bit more efficient by copying points to values rather
than values.
2013-10-28 18:52:26 +01:00
Eelco Dolstra 6123144933 Drop Cygwin and Solaris builds 2013-10-28 11:56:37 +00:00
Eelco Dolstra 1dacd427cd Update release notes, set version for 1.6.1 release 2013-10-28 11:56:21 +00:00
Eelco Dolstra ea6bf0c21f Slightly optimize listToAttrs 2013-10-28 07:34:44 +01:00
Eelco Dolstra 36e67ff16b Undocument obsolete form of "let" 2013-10-24 22:06:39 +02:00
Eelco Dolstra fba17a9043 Doc fix 2013-10-24 22:05:58 +02:00
Eelco Dolstra 2d9bb56e55 Fix segfault on Darwin
Ever since SQLite in Nixpkgs was updated to 3.8.0.2, Nix has randomly
segfaulted on Darwin:

  http://hydra.nixos.org/build/6175515
  http://hydra.nixos.org/build/6611038

It turns out that this is because the binary cache substituter somehow
ends up loading two versions of SQLite: the one in Nixpkgs and the
other from /usr/lib/libsqlite3.dylib.  It's not exactly clear why the
latter is loaded, but it appears to be because WWW::Curl indirectly loads
/System/Library/Frameworks/CoreFoundation.framework/Versions/A/CoreFoundation,
which in turn seems to load /usr/lib/libsqlite3.dylib.  This leads to
a segfault when Perl exits:

  #0  0x00000001010375f4 in sqlite3_finalize ()
  #1  0x000000010125806e in sqlite_st_destroy ()
  #2  0x000000010124bc30 in XS_DBD__SQLite__st_DESTROY ()
  #3  0x00000001001c8155 in XS_DBI_dispatch ()
  ...
  #14 0x0000000100023224 in perl_destruct ()
  #15 0x0000000100000d6a in main ()
  ...

The workaround is to explicitly load DBD::SQLite before WWW::Curl.
2013-10-24 19:15:52 +02:00
Eelco Dolstra 5bc41d78ff Rename "attribute sets" to "sets"
We don't have any other kind of sets so calling them attribute sets is
unnecessarily verbose.
2013-10-24 16:41:04 +02:00
Eelco Dolstra 9e4bb20455 Manual: Fix broken URLs
Fixes #172.
2013-10-24 16:02:08 +02:00
Eelco Dolstra dc341811d6 Add rpm_fedora19i386 to the release-critical builds 2013-10-24 15:54:23 +02:00
Eelco Dolstra 69befd33a9 Remove unnecessary call to forceStringNoCtx 2013-10-24 03:08:34 +02:00
Eelco Dolstra a5684e09d3 Document typeOf 2013-10-24 02:56:00 +02:00
Eelco Dolstra 411a3461dc Add a test of the type primops 2013-10-24 02:51:28 +02:00
Eelco Dolstra 05d02f798f Add a typeOf primop
We already have some primops for determining the type of a value, such
as isString, but they're incomplete: for instance, there is no isPath.
Rather than adding more isBla functions, the generic typeOf function
returns a string representing the type of the argument (e.g. "int").
2013-10-24 02:49:13 +02:00
Eelco Dolstra 6da92d96ae Document NIX_SHOW_STATS and NIX_COUNT_CALLS 2013-10-24 02:22:24 +02:00