Commit graph

572 commits

Author SHA1 Message Date
Shea Levy
049a379ec6 The expr of AttrNames/DynamicAttrDefs is always an ExprConcatStrings 2014-03-10 10:14:50 +01:00
Shea Levy
908e9ce259 If a dynamic attribute name evaluates to null, remove it from the set 2014-03-10 10:14:50 +01:00
Eelco Dolstra
2caab81660 Revert "Make ifs and asserts tail-recursive"
This reverts commit 273322c773.
2014-03-05 16:18:13 +01:00
Eelco Dolstra
c9f6232304 Correctly detect infinite recursion in function application
If we're evaluating some application ‘v = f x’, we can't store ‘f’
temporarily in ‘v’, because if ‘f x’ refers to ‘v’, it will get ‘f’
rather than an infinite recursion error.

Unfortunately, this breaks the tail call optimisation introduced in
c897bac549.

Fixes #217.
2014-02-27 21:47:59 +01:00
Eelco Dolstra
f14ef84a51 Warn about missing -I paths
Fixes #121.  Note that we don't warn about missing $NIX_PATH entries
because it's intended that some may be missing (cf. the default
$NIX_PATH on NixOS, which includes paths like /etc/nixos/nixpkgs for
backward compatibility).
2014-02-26 15:21:56 +01:00
Shea Levy
a7e70518b8 lexer-tab.o and parser-tab.o require each other's headers 2014-02-18 17:31:30 +01:00
Eelco Dolstra
844d83352c More "make dist" fixes 2014-02-01 15:18:48 +01:00
Eelco Dolstra
6ef32bddc1 Fix "make dist" 2014-02-01 14:38:12 +01:00
Eelco Dolstra
0c6d62cf27 Remove Automakefiles 2014-02-01 13:54:38 +01:00
Eelco Dolstra
16e7d69209 Update Makefile variable names 2014-02-01 13:54:38 +01:00
Eelco Dolstra
e0234dfddc Rename Makefile -> local.mk 2014-01-30 12:11:06 +01:00
Eelco Dolstra
94f9c14d52 Fix some clang warnings 2014-01-21 18:29:55 +01:00
Eelco Dolstra
68cde53c47 Fix building against Bison 3.0.2 2014-01-21 15:34:04 +01:00
Eelco Dolstra
81628a6ccc Merge branch 'master' into make
Conflicts:
	src/libexpr/eval.cc
2014-01-21 15:30:01 +01:00
Shea Levy
f5e5793cd2 Bare dynamic attrs: Match interpolation semantics
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-01-14 14:00:15 +01:00
Shea Levy
f9913f4422 Allow "bare" dynamic attrs
Now, in addition to a."${b}".c, you can write a.${b}.c (applicable
wherever dynamic attributes are valid).

Signed-off-by: Shea Levy <shea@shealevy.com>
2014-01-14 14:00:15 +01:00
Eelco Dolstra
b4c684e0f9 Update Makefiles 2014-01-09 16:53:47 +01:00
Shea Levy
cd49fe4f9b Don't use any syntactic sugar for dynamic attrs
This doesn't change any functionality but moves some behavior out of the
parser and into the evaluator in order to simplify the code.

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-31 23:56:26 +00:00
Shea Levy
6f3a51809a Fold dynamic binds handling into addAttr
Since addAttr has to iterate through the AttrPath we pass it, it makes
more sense to just iterate through the AttrNames in addAttr instead. As
an added bonus, this allows attrsets where two dynamic attribute paths
have the same static leading part (see added test case for an example
that failed previously).

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-12-31 17:57:10 -05:00
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
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
7ce0e05ad8 Rename Makefile.new -> Makefile 2013-11-25 15:25:13 +00:00
Eelco Dolstra
2bd0fcc966 Use libnix as a prefix for all Nix libraries
In particular "libutil" was always a problem because it collides with
Glibc's libutil.  Even if we install into $(libdir)/nix, the linker
sometimes got confused (e.g. if a program links against libstore but
not libutil, then ld would report undefined symbols in libstore
because it was looking at Glibc's libutil).
2013-11-23 23:53:41 +00:00
Eelco Dolstra
5a1114ecdb Drop the dependency on libgc in libmain
Instead, libexpr now depends on libgc.  This means commands like
nix-store that don't do any evaluation no longer require libgc.
2013-11-23 20:19:36 +00:00
Eelco Dolstra
06a8ac96e7 Initialise Boehm GC only once 2013-11-23 20:15:57 +00:00
Eelco Dolstra
90dfb37f14 Allow (dynamic) libraries to depend on other libraries 2013-11-23 20:11:02 +00:00
Eelco Dolstra
611868a909 Implement basic ‘make install’ 2013-11-23 17:04:27 +00:00
Eelco Dolstra
754c05ed6c Rename $(here) to $(d) for brevity, and remove trailing slash 2013-11-22 16:45:52 +00:00
Eelco Dolstra
1474ecfe42 Generate the parser and the lexer 2013-11-22 16:22:31 +01:00
Eelco Dolstra
b8e9efc476 New non-recursive, plain Make-based build system 2013-11-22 15:54:18 +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
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
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
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
ea6bf0c21f Slightly optimize listToAttrs 2013-10-28 07:34:44 +01:00
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
69befd33a9 Remove unnecessary call to forceStringNoCtx 2013-10-24 03:08:34 +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