1 files changed, 34 insertions, 21 deletions

diff --git a/src/nix/installables.hh b/src/nix/installables.hh
index a58f7dc59..5f0b0a292 100644
--- a/src/nix/installables.hh
+++ b/src/nix/installables.hh
@@ -1,48 +1,61 @@
 #pragma once
 
 #include "args.hh"
+#include "command.hh"
 
 namespace nix {
 
-struct UserEnvElem
-{
-    Strings attrPath;
+struct Value;
+class EvalState;
+class Expr;
 
-    // FIXME: should use boost::variant or so.
-    bool isDrv;
+struct Installable
+{
+    virtual std::string what() = 0;
 
-    // Derivation case:
-    Path drvPath;
-    StringSet outputNames;
+    virtual PathSet toBuildable()
+    {
+        throw Error("argument ‘%s’ cannot be built", what());
+    }
 
-    // Non-derivation case:
-    PathSet outPaths;
+    virtual Value * toValue(EvalState & state)
+    {
+        throw Error("argument ‘%s’ cannot be evaluated", what());
+    }
 };
 
-typedef std::vector<UserEnvElem> UserEnvElems;
-
-struct Value;
-class EvalState;
-
-struct MixInstallables : virtual Args
+struct MixInstallables : virtual Args, StoreCommand
 {
-    Strings installables;
+    std::vector<std::shared_ptr<Installable>> installables;
     Path file;
 
     MixInstallables()
     {
         mkFlag('f', "file", "file", "evaluate FILE rather than the default", &file);
-        expectArgs("installables", &installables);
+        expectArgs("installables", &_installables);
     }
 
-    UserEnvElems evalInstallables(ref<Store> store);
-
     /* Return a value representing the Nix expression from which we
        are installing. This is either the file specified by ‘--file’,
        or an attribute set constructed from $NIX_PATH, e.g. ‘{ nixpkgs
        = import ...; bla = import ...; }’. */
-    Value * buildSourceExpr(EvalState & state);
+    Value * getSourceExpr(EvalState & state);
+
+    std::vector<std::shared_ptr<Installable>> parseInstallables(ref<Store> store, Strings installables);
+
+    PathSet buildInstallables(ref<Store> store, bool dryRun);
+
+    ref<EvalState> getEvalState();
+
+    void prepare() override;
+
+private:
+
+    Strings _installables;
+
+    std::shared_ptr<EvalState> evalState;
 
+    Value * vSourceExpr = 0;
 };
 
 }