Commit graph

280 commits

Author SHA1 Message Date
Eelco Dolstra
ef8bd919fc * Implement `...' and default function arguments. 2010-03-25 12:45:23 +00:00
Eelco Dolstra
8a10360c91 * Simplify @-patterns: only {attrs}@name' or name@{attrs}' are now
allowed.  So `name1@name2', `{attrs1}@{attrs2}' and so on are now no
  longer legal.  This is no big loss because they were not useful
  anyway.

  This also changes the output of builtins.toXML for @-patterns
  slightly.
2010-03-25 12:19:41 +00:00
Eelco Dolstra
7482349fe8 * Implemented attribute set pattern matches. 2010-03-24 23:40:00 +00:00
Eelco Dolstra
0fd3648d34 * Store values in environments. 2010-03-24 12:41:08 +00:00
Eelco Dolstra
b70bd8fe56 * Reduce the number of value allocations in eval() by moving
responsibility for allocation of the result to the caller.
2010-03-24 12:11:38 +00:00
Eelco Dolstra
d31c59eb17 * Plain lambdas. 2010-03-24 11:06:05 +00:00
Eelco Dolstra
0910ae9568 * Start of an evaluator that uses call-by-need (with thunk updating)
instead of (memoised) call-by-name.
2010-03-23 17:30:50 +00:00
Nicolas Pierron
741b7577c1 Merge r20344 & r20346. 2010-03-14 11:58:07 +00:00
Eelco Dolstra
327a232c85 * Remove support for old (before Nix 0.12pre12020) databases. 2009-11-06 01:15:44 +00:00
Eelco Dolstra
deb342fb08 * builtins.trace: in the common case that the value is a string, then
show the string, not the ATerm, so we get `trace: bla' instead of
  `trace: Str("bla",[])'.
2009-10-22 08:10:12 +00:00
Eelco Dolstra
437077c39d * Added a primop unsafeDiscardOutputDependency needed by Disnix to
pass derivation paths to a builder without actually building them.
2009-10-21 15:05:30 +00:00
Eelco Dolstra
1332dd1ed3 * tryEval shouldn't catch all exceptions of type Error, since not all
of them leave the evaluator in a continuable state.  Also, it should
  be less chatty.
2009-09-23 19:19:26 +00:00
Eelco Dolstra
0dbd4638e0 * Two primops: builtins.intersectAttrs and builtins.functionArgs.
intersectAttrs returns the (right-biased) intersection between two
  attribute sets, e.g. every attribute from the second set that also
  exists in the first.  functionArgs returns the set of attributes
  expected by a function.

  The main goal of these is to allow the elimination of most of
  all-packages.nix.  Most package instantiations in all-packages.nix
  have this form:

    foo = import ./foo.nix {
      inherit a b c;
    };

  With intersectAttrs and functionArgs, this can be written as:

    foo = callPackage (import ./foo.nix) { };

  where

   callPackage = f: args:
     f ((builtins.intersectAttrs (builtins.functionArgs f) pkgs) // args);

  I.e., foo.nix is called with all attributes from "pkgs" that it
  actually needs (e.g., pkgs.a, pkgs.b and pkgs.c).  (callPackage can
  do any other generic package-level stuff we might want, such as
  applying makeOverridable.)  Of course, the automatically supplied
  arguments can be overriden if needed, e.g.

    foo = callPackage (import ./foo.nix) {
      c = c_version_2;
    };

  but for the vast majority of packages, this won't be needed.

  The advantages are to reduce the amount of typing needed to add a
  dependency (from three sites to two), and to reduce the number of
  trivial commits to all-packages.nix.  For the former, there have
  been two previous attempts:

    - Use "args: with args;" in the package's function definition.
      This however obscures the actual expected arguments of a
      function, which is very bad.

    - Use "{ arg1, arg2, ... }:" in the package's function definition
      (i.e. use the ellipis "..." to allow arbitrary additional
      arguments), and then call the function with all of "pkgs" as an
      argument.  But this inhibits error detection if you call it with
      an misspelled (or obsolete) argument.
2009-09-15 13:01:46 +00:00
Michael Raskin
3bca8931e8 Adding tryEval builtin. It allows to catch presence of errors in an expression. 2009-08-25 16:06:46 +00:00
Eelco Dolstra
749dd97a54 * Support integers and lists of strings in meta fields. This is
useful for fields like meta.maintainers, meta.priority (which can be
  a proper integer now) and even meta.license (if there are multiple
  licenses).
2009-06-30 15:53:39 +00:00
Eelco Dolstra
f2c3fc5191 * Don't show trace information by default (`--show-trace' to enable).
NixOS evaluation errors in particular look intimidating and
  generally aren't very useful.  Ideally the builtins.throw messages
  should be self-contained.
2009-06-30 13:28:29 +00:00
Eelco Dolstra
a64bbe049e * Change the scoping of "inherit (e) ..." in recs so that the
attributes of the rec are in scope of `e'.  This is useful in
  expressions such as

    rec {
      lib = import ./lib;
      inherit (lib) concatStrings;
    }

  It does change the semantics of expressions such as

    let x = {y = 1;}; in rec { x = {y = 2;}; inherit (x) y; }.y

  This now returns 2 instead of 1.  However, no code in Nixpkgs or
  NixOS seems to rely on the old behaviour.
2009-05-15 13:46:13 +00:00
Eelco Dolstra
d407d572fd * Some syntactic sugar for attribute sets: allow {x.y.z = ...;} as a
shorthand for {x = {y = {z = ...;};};}.  This is especially useful
  for NixOS configuration files, e.g.

    {
      services = {
        sshd = {
          enable = true;
          port = 2022;
        };
      };
    }

  can now be written as

    {
      services.sshd.enable = true;
      services.sshd.port = 2022;
    }

  However, it is currently not permitted to write
  
    {
      services.sshd = {enable = true;};
      services.sshd.port = 2022;
    }

  as this is considered a duplicate definition of `services.sshd'.
2009-05-15 12:35:23 +00:00
Eelco Dolstra
e42975490f * Check for duplicate attributes in fixAttrs, rather than doing a
separate traversal after parsing.  Likewise, check for duplicate
  pattern variables right away.
2009-05-14 14:29:45 +00:00
Eelco Dolstra
50d11b90ca * Allow unsafe (unspecified) comparisons between attrsets unless
NIX_NO_UNSAFE_EQ is set, for now.
2009-05-12 11:06:24 +00:00
Eelco Dolstra
c34e6d71bc * Disallow equality tests between attribute sets. This was always
broken, but now the evaluator checks for it to prevent Nix
  expressions from relying on undefined behaviour.  Equality tests are
  implemented using a shallow pointer equality test between ATerms.
  However, because attribute sets are lazy and contain position
  information, this can give false positives.  For instance,
  previously

    let y = {x = 1;}; in y == y

  evaluated to true, while the equivalent expression

    {x = 1;} == {x = 1;}

  evaluated to false.  So disallow these tests for now.  (Eventually
  we may want to implement deep equality tests for attribute sets,
  like lib.eqStrict.)
  
* Idem: disallow comparisons between functions.

* Implemented deep comparisons of lists.  This had the same problem as
  attribute sets - the elements in the list weren't evaluated.  For
  instance,

    ["xy"] == [("x" + "y")]

  evaluated to false.  Now it works properly.
2009-05-11 15:50:14 +00:00
Eelco Dolstra
7660e2a068 * Remove a right recursion that causes the parser to barf on very long
lists.  The comment about ATreverse requiring unbounded stack space
  was unfounded anyway.
2009-05-07 11:35:52 +00:00
Eelco Dolstra
4e646b0ddb * Fix a few "comparison is always false/true due to limited range of
data type" warnings on 64-bit platforms.  The one in parser.y is
  likely to be a real bug.
2009-04-16 12:03:17 +00:00
Eelco Dolstra
2897286487 * Unify exportReferencesGraph and exportBuildReferencesGraph, and make
sure that it works as expected when you pass it a derivation.  That
  is, we have to make sure that all build-time dependencies are built,
  and that they are all in the input closure (otherwise remote builds
  might fail, for example).  This is ensured at instantiation time by
  adding all derivations and their sources to inputDrvs and inputSrcs.
2009-03-18 17:36:42 +00:00
Eelco Dolstra
d4753c944f 2009-03-06 11:01:45 +00:00
Marc Weber
1407a1ec99 added primop functions __isBool, __isString, __isInt 2009-02-05 19:35:40 +00:00
Nicolas Pierron
110606d470 Add the "addErrorContext" builtin to add more information in the stack trace. 2009-01-27 14:36:44 +00:00
Eelco Dolstra
8e39d9bdb3 * Make Nix build with Bison 2.4. 2009-01-12 12:51:28 +00:00
Eelco Dolstra
63b8f09d8d 2008-12-04 10:45:47 +00:00
Eelco Dolstra
f8713e1287 * Dirty hack to make nix-push work properly on derivations: the
derivation should be a source rather than a derivation dependency of
  the call to the NAR derivation.  Otherwise the derivation (and all
  its dependencies) will be built as a side-effect, which may not even
  succeed.
2008-12-04 10:40:41 +00:00
Eelco Dolstra
ff762fb499 * Pass HashType values instead of strings. 2008-12-03 16:10:17 +00:00
Eelco Dolstra
1307b22223 * Made addToStore() a lot more efficient: it no longer reads the path
being copied 3 times in the worst case.  It doesn't run in constant space,
  but it didn't do that anyway.
2008-12-03 15:51:17 +00:00
Eelco Dolstra
64519cfd65 * Unify the treatment of sources copied to the store, and recursive
SHA-256 outputs of fixed-output derivations.  I.e. they now produce
  the same store path:

  $ nix-store --add x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  $ nix-store --add-fixed --recursive sha256 x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  the latter being the same as the path that a derivation

    derivation {
      name = "x";
      outputHashAlgo = "sha256";
      outputHashMode = "recursive";
      outputHash = "...";
      ...
    };

  produces.

  This does change the output path for such fixed-output derivations.
  Fortunately they are quite rare.  The most common use is fetchsvn
  calls with SHA-256 hashes.  (There are a handful of those is
  Nixpkgs, mostly unstable development packages.)
  
* Documented the computation of store paths (in store-api.cc).
2008-12-03 15:06:30 +00:00
Eelco Dolstra
aab530e971 * Primop builtins.storePath for declaring a store path as a
dependency.  `storePath /nix/store/bla' gives exactly the same
  result as `toPath /nix/store/bla', except that the former includes
  /nix/store/bla in the dependency context of the string.

  Useful in some generated Nix expressions like nix-push, which now
  finally does the right thing wrt distributed builds.  (Previously
  the path to be packed wasn't an explicit dependency, so it wouldn't
  be copied to the remote machine.)
2008-11-19 23:26:19 +00:00
Eelco Dolstra
99dc3e613a * Require that __overrides is defined as a non-recursive attribute
(which means it can only be defined via "inherit"), otherwise we get
  scoping bugs, since __overrides can't be recursive (or at least, it
  would be hard).
2008-08-26 14:05:59 +00:00
Eelco Dolstra
abec1c0004 * Evaluate attributes in sorted order for better determinism. 2008-08-25 14:31:29 +00:00
Eelco Dolstra
c4f1c2114b * Minor simplification. 2008-08-25 14:15:56 +00:00
Michael Raskin
b7ff182b6e Fixing an obvious typo in override code. I do not know whether it works correctly after the change, but at least it ca nbe compiled now. 2008-08-14 22:01:43 +00:00
Eelco Dolstra
ca07f3e370 * Another experimental feature: a way to truly override attributes in
a rec.  This will be very useful to allow end-user customisation of
  all-packages.nix, for instance globally overriding GCC or some other
  dependency.  The // operator doesn't cut it: you could replace the
  "gcc" attribute, but all other attributes would continue to
  reference the original value due to the substitution semantics of
  rec.

  The syntax is a bit hacky but this is to allow backwards
  compatibility.
2008-08-14 16:59:37 +00:00
Eelco Dolstra
9279174dde * Added an experimental feature suggested by Andres: ellipses ("...")
in attribute set pattern matches.  This allows defining a function
  that takes *at least* the listed attributes, while ignoring
  additional attributes.  For instance,

    {stdenv, fetchurl, fuse, ...}:
    
    stdenv.mkDerivation {
      ...
    };
    
  defines a function that requires an attribute set that contains the 
  specified attributes but ignores others.  The main advantage is that
  we can then write in all-packages.nix

    aefs = import ../bla/aefs pkgs;

  instead of

    aefs = import ../bla/aefs {
      inherit stdenv fetchurl fuse;
    };

  This saves a lot of typing (not to mention not having to update
  all-packages.nix with purely mechanical changes).  It saves as much
  typing as the "args: with args;" style, but has the advantage that
  the function arguments are properly declared (not implicit in what
  the body of the "with" uses).
2008-08-14 14:00:44 +00:00
Eelco Dolstra
1b962fc720 * @-patterns as in Haskell. For instance, in a function definition
f = args @ {x, y, z}: ...;

  `args' refers to the argument as a whole, which is further
  pattern-matched against the attribute set pattern {x, y, z}.
2008-08-14 12:53:29 +00:00
Eelco Dolstra
e818838412 * "pattern" non-terminal. 2008-08-14 10:14:34 +00:00
Eelco Dolstra
efe4b690ae * Refactoring: combine functions that take an attribute set and
functions that take a single argument (plain lambdas) into one AST
  node (Function) that contains a Pattern node describing the
  arguments.  Current patterns are single lazy arguments (VarPat) and
  matching against an attribute set (AttrsPat).

  This refactoring allows other kinds of patterns to be added easily,
  such as Haskell-style @-patterns, or list pattern matching.
2008-08-14 10:04:22 +00:00
Eelco Dolstra
5664b6d7ba * Removed the "valid values" feature. Nobody uses it anyway. 2008-08-11 13:36:40 +00:00
Eelco Dolstra
fc691e1cbd * Print a better error message when a non-derivation attribute set is
coerced to a string.
2008-07-24 14:52:25 +00:00
Eelco Dolstra
7cd88b1dec * Generalised the dependencyClosure primop to builtins.genericClosure,
which is hopefully more useful.
* New primops: length, mul, div.
2008-07-11 13:29:04 +00:00
Eelco Dolstra
d567baabbd * Export the nix-env derivation name parsing and version comparison
logic through the `parseDrvName' and `compareVersions' primops.
  This will allow expressions to easily check whether some dependency
  is a specific needed version or falls in some version range.  See
  tests/lang/eval-okay-versions.nix for examples.
2008-07-01 10:10:32 +00:00
Sander van der Burg
c41a3ec3a9 First attempt to update Nix SDF grammar to match the actual bison grammar 2008-06-04 14:36:46 +00:00
Eelco Dolstra
bd955e15e1 * GCC 4.3.0 (Fedora 9) compatibility fixes. Reported by Gour and
Armijn Hemel.
2008-05-21 11:17:31 +00:00
Eelco Dolstra
2f1e2cf632 * Note that the SDF grammar isn't used. 2008-03-20 14:59:33 +00:00