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.
out the AST as an ATerm.
* Mode `--eval-only' to parse and evaluate the input, and print the
resulting normal form as an ATerm.
Neither of these modes require store/DB write permission.
The expression `with E1; E2' evaluates to E2 with all bindings in
the attribute set E1 substituted. E.g.,
with {x = 123;}; x
evaluates to 123. That is, the attribute set E1 is in scope in E2.
This is particularly useful when importing files containing lots
definitions. E.g., instead of
let {
inherit (import ./foo.nix) a b c d e f;
body = ... a ... f ...;
}
we can now say
with import ./foo.nix;
... a ... f ...
I.e., we don't have to say what variables should be brought into scope.
permission to the Nix store or database. E.g., `nix-env -qa' will
work, but `nix-env -qas' won't (the latter needs DB access). The
option `--readonly-mode' forces this mode; otherwise, it's only
activated when the database cannot be opened.
derivation, since NormalisationGoal would first run a
NormalisationGoal on the subderivation (a no-op, since in a
situation where we need fallback the successor is known), and then
runs a RealisationGoal on the normal form, which then cannot do a
fallback because it doesn't know the derivation expression for which
it is a normal form.
Tossed out the 2-phase normalisation/realisation in
NormalisationGoal and SubstitutionGoal since it's no longer needed -
a RealisationGoal will run a NormalisationGoal if necessary.
profile. Arguments are either generation number, or `old' to delete
all non-current generations. Typical use:
$ nix-env --delete-generations old
$ nix-collect-garbage
* istringstream -> string2Int.
