diff options
author | Eelco Dolstra <e.dolstra@tudelft.nl> | 2008-08-14 14:00:44 +0000 |
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committer | Eelco Dolstra <e.dolstra@tudelft.nl> | 2008-08-14 14:00:44 +0000 |
commit | 9279174dde3e1a450e63e866d2683352dd8238d3 (patch) | |
tree | 05b5b835f143b97d150a37873641fb5d5e9a7075 /src/libexpr/nixexpr.hh | |
parent | db4f4a842515392a6b40f5c86b2ef885c1278451 (diff) |
* 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).
Diffstat (limited to 'src/libexpr/nixexpr.hh')
-rw-r--r-- | src/libexpr/nixexpr.hh | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh index 320d1dc97..43ac19f92 100644 --- a/src/libexpr/nixexpr.hh +++ b/src/libexpr/nixexpr.hh @@ -24,6 +24,7 @@ typedef ATerm Expr; typedef ATerm DefaultValue; typedef ATerm Pos; typedef ATerm Pattern; +typedef ATerm ATermBool; /* A STL vector of ATerms. Should be used with great care since it's |