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2009-05-12 * Allow unsafe (unspecified) comparisons between attrsets unlessEelco Dolstra1-1/+7
NIX_NO_UNSAFE_EQ is set, for now.
2009-05-11 * Disallow equality tests between attribute sets. This was alwaysEelco Dolstra1-6/+42
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.
2008-08-26 * Require that __overrides is defined as a non-recursive attributeEelco Dolstra1-1/+1
(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).
2008-08-14 Fixing an obvious typo in override code. I do not know whether it works ↵Michael Raskin1-1/+1
correctly after the change, but at least it ca nbe compiled now.
2008-08-14 * Another experimental feature: a way to truly override attributes inEelco Dolstra1-2/+24
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 * Added an experimental feature suggested by Andres: ellipses ("...")Eelco Dolstra1-5/+7
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 * @-patterns as in Haskell. For instance, in a function definitionEelco Dolstra1-42/+47
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 * Refactoring: combine functions that take an attribute set andEelco Dolstra1-70/+82
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.
2008-08-11 * Removed the "valid values" feature. Nobody uses it anyway.Eelco Dolstra1-44/+5
2008-07-24 * Print a better error message when a non-derivation attribute set isEelco Dolstra1-3/+10
coerced to a string.
2007-05-16 * New builtin function "isFunction". You're not supposed to use itEelco Dolstra1-1/+1
;-) * Channels: fix channels that are plain lists of derivations (like strategoxt-unstable) instead of functions (like nixpkgs-unstable). This fixes the error message "error: the left-hand side of the function call is neither a function nor a primop (built-in operation) but a list".
2007-04-16 * New primop "throw <string>" to throw an error. This is like abort,Eelco Dolstra1-0/+3
only thrown errors are caught by the top-level derivation evaluation in nix-env -qa / -i.
2007-02-27 * Greatly reduced the amount of stack space used by the Nix expressionEelco Dolstra1-188/+274
evaluator. This was important because the NixOS expressions started to hit 2 MB default stack size on Linux. GCC is really dumb about stack space: it just adds up all the local variables and temporaries of every scope into one huge stack frame. This is really bad for deeply recursive functions. For instance, every `throw Error(format("error message"))' causes a format object of a few hundred bytes to be allocated on the stack. As a result, every recursive call to evalExpr2() consumed 4680 bytes. By splitting evalExpr2() and by moving the exception-throwing code out of the main functions, evalExpr2() now only consumes 40 bytes. Similar for evalExpr().
2007-02-27 * When NIX_SHOW_STATS=1, show the amount of stack space consumed byEelco Dolstra1-2/+10
the Nix expression evaluator.
2007-01-13 * Memoize strict evaluation.Eelco Dolstra1-11/+28
2007-01-13 * Make printing an expression as XML interruptible.Eelco Dolstra1-0/+4
2007-01-13 * Cleanup.Eelco Dolstra1-6/+6
2006-12-01 * Merge addToStore and addToStoreFixed.Eelco Dolstra1-1/+4
* addToStore now adds unconditionally, it doesn't use readOnlyMode. Read-only operation is up to the caller (who can call computeStorePathForPath).
2006-11-30 * Refactoring. There is now an abstract interface class StoreAPIEelco Dolstra1-2/+2
containing functions that operate on the Nix store. One implementation is LocalStore, which operates on the Nix store directly. The next step, to enable secure multi-user Nix, is to create a different implementation RemoteStore that talks to a privileged daemon process that uses LocalStore to perform the actual operations.
2006-10-17 * Print out the offending path.Eelco Dolstra1-2/+3
2006-10-17 * An awful backwards compatibility hack.Eelco Dolstra1-0/+24
2006-10-17 * Do the path check on the normal form.Eelco Dolstra1-2/+5
2006-10-16 * Big cleanup of the semantics of paths, strings, contexts, stringEelco Dolstra1-95/+115
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'.)
2006-10-11 * Removed URIs from the evaluator (NIX-66). They are now just anotherEelco Dolstra1-3/+1
kind of notation for strings.
2006-10-10 * Quick hack to fix NIX-67: evaluation result differing if the NixEelco Dolstra1-4/+8
expression resides in the store.
2006-10-03 * toFile: added an additional argument to specify the store pathEelco Dolstra1-1/+6
suffix, e.g., `builtins.toFile "builder.sh" "..."'. * toFile: handle references to other files correctly.
2006-09-24 * The result of a concatenation with a derivation on the left-handEelco Dolstra1-0/+1
side should be a path, I guess. * Handle paths that are in the store but not direct children of the store directory. * Ugh, hack to prevent double context wrapping.
2006-09-22 * Builtin function `add' to add integers.Eelco Dolstra1-0/+10
* Put common test functions in tests/lang/lib.nix.
2006-09-04 * Use a proper namespace.Eelco Dolstra1-1/+9
* Optimise header file usage a bit. * Compile the parser as C++.
2006-08-30 * Okay, that's a bit harder than expected.Eelco Dolstra1-7/+14
2006-08-30 * Uninitialised variable.Eelco Dolstra1-1/+1
2006-08-29 * Fix the ~ operator.Eelco Dolstra1-2/+12
2006-08-28 * Removed processBinding, instead we now apply toString to allEelco Dolstra1-1/+1
derivation attributes to flatten them into strings. This is possible since string can nowadays be wrapped in contexts that describe the derivations/sources referenced by the evaluation of the string.
2006-08-24 * Strict evaluation and XML printing of lists.Eelco Dolstra1-3/+9
2006-08-24 * Refactoring: move strictEval to libexpr.Eelco Dolstra1-0/+43
2006-08-23 * New primop: abort "error message".Eelco Dolstra1-2/+2
2006-08-04 * Fix a few warnings.Eelco Dolstra1-1/+1
2006-07-28 * `nix-instantiate ... --arg NAME VALUE': allow arguments to be passedEelco Dolstra1-4/+11
to functions from the command line. * nix-build: started removing backticks.
2006-07-26 * Refactoring: get the selection path stuff out of getDerivations()Eelco Dolstra1-1/+21
and put it into a separate function findAlongAttrPath().
2006-07-24 * When there is a domain check, we have to evaluate the argument.Eelco Dolstra1-0/+1
Can't be lazy!
2006-07-24 * New language feature: domain checks, which check whether a functionEelco Dolstra1-8/+27
argument has a valid value, i.e., is in a certain domain. E.g., { foo : [true false] , bar : ["a" "b" "c"] }: ... This previously could be done using assertions, but domain checks will allow the buildfarm to automatically extract the configuration space from functions.
2006-07-24 * Refactoring to support domain checks.Eelco Dolstra1-5/+7
2006-07-19 * Better error messages (especially wrt types).Eelco Dolstra1-27/+37
2006-05-08 * Allow function argument default values to refer to other argumentsEelco Dolstra1-35/+40
of the function. Implements NIX-45.
2006-05-08 * Show evaluation stats when NIX_SHOW_STATS=1.Eelco Dolstra1-1/+4
2006-05-04 * Use the new ATermMap.Eelco Dolstra1-23/+21
2006-05-02 * Optimise null-ary term builders. Also declare all term builderEelco Dolstra1-5/+2
functions as pure, which might improve performance a bit.
2006-05-02 * Use a linked list of substitutions. This reduces the amount ofEelco Dolstra1-4/+7
copying.
2006-05-02 * Some preliminaries towards NIX-45.Eelco Dolstra1-3/+23
2006-05-01 * String interpolation. Expressions likeEelco Dolstra1-1/+9
"--with-freetype2-library=" + freetype + "/lib" can now be written as "--with-freetype2-library=${freetype}/lib" An arbitrary expression can be enclosed within ${...}, not just identifiers. * Escaping in string literals: \n, \r, \t interpreted as in C, any other character following \ is interpreted as-is. * Newlines are now allowed in string literals.