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27 commits

Author SHA1 Message Date
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 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 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 5f2492eaec * New primop "throw <string>" to throw an error. This is like abort,
only thrown errors are caught by the top-level derivation evaluation
  in nix-env -qa / -i.
2007-04-16 15:03:19 +00:00
Eelco Dolstra 451dbf687f * nix-env now maintains meta info (from the `meta' derivation
attribute) about installed packages in user environments.  Thus, an
  operation like `nix-env -q --description' shows useful information
  not only on available packages but also on installed packages.

* nix-env now passes the entire manifest as an argument to the Nix
  expression of the user environment builder (not just a list of
  paths), so that in particular the user environment builder has
  access to the meta attributes.
  
* New operation `--set-flag' in nix-env to change meta info of
  installed packages.  This will be useful to pass per-package
  policies to the user environment builder (e.g., how to resolve
  collision or whether to disable a package (NIX-80)) or upgrade
  policies in nix-env (e.g., that a package should be "masked", that
  is, left untouched by upgrade actions).  Example:

  $ nix-env --set-flag enabled false ghc-6.4
2007-02-02 01:52:42 +00:00
Eelco Dolstra f23dcdd603 * Canonicalise ASTs in `nix-instantiate --eval': remove position
info, sort attribute sets.
2007-01-13 16:17:07 +00:00
Eelco Dolstra d7efd76394 * Big cleanup of the semantics of paths, strings, contexts, string
concatenation and string coercion.  This was a big mess (see
  e.g. NIX-67).  Contexts are now folded into strings, so that they
  don't cause evaluation errors when they're not expected.  The
  semantics of paths has been clarified (see nixexpr-ast.def).
  toString() and coerceToString() have been merged.

  Semantic change: paths are now copied to the store when they're in a
  concatenation (and in most other situations - that's the
  formalisation of the meaning of a path).  So

    "foo " + ./bla

  evaluates to "foo /nix/store/hash...-bla", not "foo
  /path/to/current-dir/bla".  This prevents accidental impurities, and
  is more consistent with the treatment of derivation outputs, e.g.,
  `"foo " + bla' where `bla' is a derivation.  (Here `bla' would be
  replaced by the output path of `bla'.)
2006-10-16 15:55:34 +00:00
Eelco Dolstra 1bdc152931 * Shut up a warning. 2006-09-20 16:36:29 +00:00
Eelco Dolstra 4be5443882 * Remove unnecessary inclusions of aterm2.h. 2006-09-04 22:08:40 +00:00
Eelco Dolstra 75068e7d75 * Use a proper namespace.
* Optimise header file usage a bit.
* Compile the parser as C++.
2006-09-04 21:06:23 +00:00
Eelco Dolstra 38f18aa6d4 * New primop: abort "error message". 2006-08-23 15:46:00 +00:00
Eelco Dolstra 1854f84e83 * Fix a few warnings. 2006-08-04 17:07:13 +00:00
Eelco Dolstra c11839d7b2 * `nix-instantiate --print-args': print out the valid values for
functions arguments that have a domain.
2006-07-28 14:01:29 +00:00
Eelco Dolstra 57751fdb55 * Refactoring to support domain checks. 2006-07-24 15:16:03 +00:00
Eelco Dolstra 4f3725b167 * Better error messages (especially wrt types). 2006-07-19 15:36:15 +00:00
Eelco Dolstra 0832956089 * Use the new ATermMap. 2006-05-04 12:21:08 +00:00
Eelco Dolstra 68174bdc7d * Use a linked list of substitutions. This reduces the amount of
copying.
2006-05-02 21:39:02 +00:00
Eelco Dolstra fa72ae1e9c * GCC 4.1 compatibility. 2006-03-06 14:40:10 +00:00
Eelco Dolstra 426593162e * ATermMap needs an assignment operator, otherwise we are screwed. 2005-05-08 10:28:19 +00:00
Eelco Dolstra c9c58dba55 * Primop `__currentSystem' to return the current platform identifier. 2005-04-10 17:38:19 +00:00
Eelco Dolstra 5fe9222b36 * Don't use ATmake / ATmatch anymore, nor the ATMatcher class.
Instead we generate data bindings (build and match functions) for
  the constructors specified in `constructors.def'.  In particular
  this removes the conversions between AFuns and strings, and Nix
  expression evaluation now seems 3 to 4 times faster.
2004-10-26 22:54:26 +00:00
Eelco Dolstra 9fa07b376d * String/path concatenation operator (`+'). 2004-10-26 17:01:35 +00:00
Eelco Dolstra bbfdd64741 * Allow primops with more that 1 arguments. 2004-08-04 10:59:20 +00:00
Eelco Dolstra 59b94ee18a * When something goes wrong in the evaluation of a Nix expression,
print a nice backtrace of the stack, rather than vomiting a gigantic
  (and useless) aterm on the screen.  Example:

    error: while evaluating file `.../pkgs/system/test.nix':
    while evaluating attribute `subversion' at `.../pkgs/system/all-packages-generic.nix', line 533:
    while evaluating function at `.../pkgs/applications/version-management/subversion/default.nix', line 1:
    assertion failed at `.../pkgs/applications/version-management/subversion/default.nix', line 13

  Since the Nix expression language is lazy, the trace may be
  misleading.  The purpose is to provide a hint as to the location of
  the problem.
2004-04-05 22:27:41 +00:00
Eelco Dolstra 9b44480612 * Use a map to lookup primops.
* Various performance improvements in the evaluator.
* Do not link against unused (and missing!) libraries (-lsglr, etc.).
2004-02-04 16:03:29 +00:00
Eelco Dolstra c4f7ae4aa5 * Verify that all variables in a Nix expression are defined. 2004-02-03 14:45:34 +00:00
Eelco Dolstra ac68840e79 * Refactoring: put the Nix expression evaluator in its own library so
that it can be used by multiple programs.
2003-11-19 11:35:41 +00:00
Renamed from src/nix-instantiate/nixexpr.hh (Browse further)