Commit graph

85 commits

Author SHA1 Message Date
Eelco Dolstra 33972629d7 Fix whitespace 2013-09-02 16:29:15 +02:00
Shea Levy afc6c1bad6 Simplify inherited attribute handling
This reduces the difference between inherited and non-inherited
attribute handling to the choice of which env to use (in recs and lets)
by setting the AttrDef::e to a new ExprVar in the parser rather than
carrying a separate AttrDef::v VarRef member.

As an added bonus, this allows inherited attributes that inherit from a
with to delay forcing evaluation of the with's attributes.

Signed-off-by: Shea Levy <shea@shealevy.com>
2013-08-26 11:31:56 +02:00
Eelco Dolstra d308aeaf53 Store Nix integers as longs
So on 64-bit systems, integers are now 64-bit.

Fixes #158.
2013-08-19 12:35:03 +02:00
Eelco Dolstra 3d77b28eac Add comparison operators ‘<’, ‘<=’, ‘>’ and ‘>=’ 2013-08-02 18:39:40 +02:00
Eelco Dolstra 47701677e8 Add integer ‘-’, ‘*’ and ‘/’ operators 2013-08-02 16:03:02 +00:00
Eelco Dolstra 5d147e125c Add a unary integer negation operator
This allows saying "-1" instead of "builtins.sub 0 1".
2013-08-02 15:43:31 +00:00
Eelco Dolstra 18a48d80a0 Show function names in error messages
Functions in Nix are anonymous, but if they're assigned to a
variable/attribute, we can use the variable/attribute name in error
messages, e.g.

while evaluating `concatMapStrings' at `/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/pkgs/lib/strings.nix:18:25':
...
2013-05-16 19:08:02 +02:00
Eelco Dolstra 804709706c Fix building against Bison 2.6 2013-03-14 18:31:08 +01:00
Eelco Dolstra bdd4646338 Revert "Prevent config.h from being clobbered"
This reverts commit 28bba8c44f.
2013-03-08 01:24:59 +01:00
Eelco Dolstra 28bba8c44f Prevent config.h from being clobbered 2013-03-07 23:55:55 +01:00
Eelco Dolstra 5f18cd2e84 Make "${./path} ..." evaluate to a string, not a path
Wacky string coercion semantics caused expressions like

  exec = "${./my-script} params...";

to evaluate to a path (‘/path/my-script params’), because
anti-quotations are desuged to string concatenation:

  exec = ./my-script + " params...";

By constrast, adding a space at the start would yield a string as
expected:

  exec = " ${./my-script} params...";

Now the first example also evaluates to a string.
2013-02-08 20:04:04 +01:00
Eelco Dolstra 767101824a Avoid concatenating lists of one string 2012-08-13 15:10:29 -04:00
Eelco Dolstra 00c98a6bef Use Bison 2.5 2012-04-13 14:28:26 +02:00
Eelco Dolstra 9d091ee99a * Handle the case where the search path element is a regular file. 2011-08-06 18:45:28 +00:00
Eelco Dolstra c7101dac0b * Allow redirections in search path entries. E.g. if you have a
directory

    /home/eelco/src/stdenv-updates

  that you want to use as the directory for import such as

    with (import <nixpkgs> { });

  then you can say

    $ nix-build -I nixpkgs=/home/eelco/src/stdenv-updates
2011-08-06 17:48:57 +00:00
Eelco Dolstra 1ecc97b6bd * Add a Nix expression search path feature. Paths between angle
brackets, e.g.

    import <nixpkgs/pkgs/lib>

  are resolved by looking them up relative to the elements listed in
  the search path.  This allows us to get rid of hacks like

    import "${builtins.getEnv "NIXPKGS_ALL"}/pkgs/lib"

  The search path can be specified through the ‘-I’ command-line flag
  and through the colon-separated ‘NIX_PATH’ environment variable,
  e.g.,

    $ nix-build -I /etc/nixos ...

  If a file is not found in the search path, an error message is
  lazily thrown.
2011-08-06 16:05:24 +00:00
Eelco Dolstra 54945a2950 * Refactoring: move parseExprFromFile() and parseExprFromString() into
the EvalState class.
2011-08-06 13:02:55 +00:00
Eelco Dolstra d5d4dcd4c9 * Allow attribute names to be strings. Based on the
allow-arbitrary-strinsg-in-names patch by Marc Weber.
2011-07-13 15:53:24 +00:00
Eelco Dolstra 0a623a10c7 * Allow a default value in attribute selection by writing
x.y.z or default

  (as originally proposed in
  https://mail.cs.uu.nl/pipermail/nix-dev/2009-September/002989.html).

  For instance, an expression like

    stdenv.lib.attrByPath ["features" "ckSched"] false args

  can now be written as

    args.features.ckSched or false
2011-07-13 12:19:57 +00:00
Eelco Dolstra 2b9e29b1c8 * Change the right-hand side of the ‘.’ operator from an attribute to
an attribute path.  This is a refactoring to support default values.
2011-07-06 12:28:57 +00:00
Eelco Dolstra 5637037802 * In the ‘?’ operator, allow attribute paths. For instance, you can
write ‘attrs ? a.b’ to test whether ‘attrs’ has an attribute ‘a’
  containing an attribute ‘b’.  This is more convenient than ‘attrs ?
  a && attrs.a ? b’.

  Slight change in the semantics: it's no longer an error if the
  left-hand side of ‘?’ is not an attribute set.  In that case it just
  returns false.  So, ‘null ? foo’ no longer throws an error.
2011-07-06 10:58:17 +00:00
Eelco Dolstra e0b7fb8f27 * Keep attribute sets in sorted order to speed up attribute lookups.
* Simplify the representation of attributes in the AST.
* Change the behaviour of listToAttrs() in case of duplicate names.
2010-10-24 19:52:33 +00:00
Eelco Dolstra b2ba62170c * Optimise string constants by putting them in the symbol table. 2010-10-23 21:11:59 +00:00
Eelco Dolstra 705868a8a9 * Make sure that config.h is included before the system headers,
because it defines _FILE_OFFSET_BITS.  Without this, on 
  OpenSolaris the system headers define it to be 32, and then 
  the 32-bit stat() ends up being called with a 64-bit "struct 
  stat", or vice versa.

  This also ensures that we get 64-bit file sizes everywhere.

* Remove the redundant call to stat() in parseExprFromFile().
  The file cannot be a symlink because that's the exit condition
  of the loop before.
2010-10-04 17:55:38 +00:00
Eelco Dolstra 01e58adce0 * Store position info for inherited attributes. 2010-05-07 12:43:57 +00:00
Eelco Dolstra 84ce7ac76f * Store attribute positions in the AST and report duplicate attribute
errors with position info.
* For all positions, use the position of the first character of the
  first token, rather than the last character of the first token plus
  one.
2010-05-06 16:46:48 +00:00
Eelco Dolstra ebade9ff8b * Check for duplicate attribute names / function arguments. `make
check' now succeeds :-)
* An attribute set such as `{ foo = { enable = true; };
  foo.port = 23; }' now parses.  It was previously rejected, but I'm
  too lazy to implement the check.  (The only reason to reject it is
  that the reverse, `{ foo.port = 23; foo = { enable = true; }; }', is
  rejected, which is kind of ugly.)
2010-04-22 11:02:24 +00:00
Eelco Dolstra 267dc693d2 * Fix builtins. 2010-04-14 22:59:39 +00:00
Eelco Dolstra 9985230c00 * After parsing, compute level/displacement pairs for each variable
use site, allowing environments to be stores as vectors of values
  rather than maps.  This should speed up evaluation and reduce the
  number of allocations.
2010-04-14 14:42:32 +00:00
Eelco Dolstra 7d47498b5e * Evaluate lets directly (i.e. without desugaring to `rec { attrs...;
<let-body> = e; }.<let-body>).  This prevents the unnecessary
  allocation of an attribute set.
2010-04-13 13:42:25 +00:00
Eelco Dolstra ac1e8f40d4 * Use a symbol table to represent identifiers and attribute names
efficiently.  The symbol table ensures that there is only one copy
  of each symbol, thus allowing symbols to be compared efficiently
  using a pointer equality test.
2010-04-13 12:25:42 +00:00
Eelco Dolstra 10e8b1fd15 * Finished the ATerm-less parser. 2010-04-12 23:33:23 +00:00
Eelco Dolstra d4f0b0fc6c * Indented strings. 2010-04-12 22:03:27 +00:00
Eelco Dolstra a60317f20f * More missing constructs. 2010-04-12 21:21:24 +00:00
Eelco Dolstra 4d6ad5be17 * Don't use ATerms for the abstract syntax trees anymore. Not
finished yet.
2010-04-12 18:30:11 +00:00
Eelco Dolstra ed711f73bc * Don't use ATerms to represent integers in the lexer. 2010-04-12 10:38:18 +00:00
Eelco Dolstra a5ece7d016 * Removed the `~' operator. 2010-04-01 16:59:07 +00:00
Eelco Dolstra 55e207b2dc * Cache parse trees to prevent repeated parsing of imported Nix
expressions.
2010-03-31 16:14:32 +00:00
Eelco Dolstra 31428c3a06 * Started integrating the new evaluator. 2010-03-29 14:37:56 +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
Nicolas Pierron 741b7577c1 Merge r20344 & r20346. 2010-03-14 11:58:07 +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 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 8e39d9bdb3 * Make Nix build with Bison 2.4. 2009-01-12 12:51:28 +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