forked from lix-project/lix
62a6eeb1f3
Nix search path lookups like <nixpkgs> are now desugared to ‘findFile
nixPath <nixpkgs>’, where ‘findFile’ is a new primop. Thus you can
override the search path simply by saying
let
nixPath = [ { prefix = "nixpkgs"; path = "/my-nixpkgs"; } ];
in ... <nixpkgs> ...
In conjunction with ‘scopedImport’ (commit
c273c15cb1
), the Nix search path can be
propagated across imports, e.g.
let
overrides = {
nixPath = [ ... ] ++ builtins.nixPath;
import = fn: scopedImport overrides fn;
scopedImport = attrs: fn: scopedImport (overrides // attrs) fn;
builtins = builtins // overrides;
};
in scopedImport overrides ./nixos
58 lines
1.3 KiB
C++
58 lines
1.3 KiB
C++
#include "common-opts.hh"
|
|
#include "../libmain/shared.hh"
|
|
#include "util.hh"
|
|
|
|
|
|
namespace nix {
|
|
|
|
|
|
bool parseOptionArg(const string & arg, Strings::iterator & i,
|
|
const Strings::iterator & argsEnd, EvalState & state,
|
|
Bindings & autoArgs)
|
|
{
|
|
if (arg != "--arg" && arg != "--argstr") return false;
|
|
|
|
UsageError error(format("`%1%' requires two arguments") % arg);
|
|
|
|
if (i == argsEnd) throw error;
|
|
string name = *i++;
|
|
if (i == argsEnd) throw error;
|
|
string value = *i++;
|
|
|
|
/* !!! check for duplicates! */
|
|
Value * v = state.allocValue();
|
|
autoArgs.push_back(Attr(state.symbols.create(name), v));
|
|
|
|
if (arg == "--arg")
|
|
state.mkThunk_(*v, state.parseExprFromString(value, absPath(".")));
|
|
else
|
|
mkString(*v, value);
|
|
|
|
autoArgs.sort(); // !!! inefficient
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
bool parseSearchPathArg(const string & arg, Strings::iterator & i,
|
|
const Strings::iterator & argsEnd, Strings & searchPath)
|
|
{
|
|
if (arg != "-I") return false;
|
|
if (i == argsEnd) throw UsageError(format("`%1%' requires an argument") % arg);;
|
|
searchPath.push_back(*i++);
|
|
return true;
|
|
}
|
|
|
|
|
|
Path lookupFileArg(EvalState & state, string s)
|
|
{
|
|
if (s.size() > 2 && s.at(0) == '<' && s.at(s.size() - 1) == '>') {
|
|
Path p = s.substr(1, s.size() - 2);
|
|
return state.findFile(p);
|
|
} else
|
|
return absPath(s);
|
|
}
|
|
|
|
|
|
}
|