Merge branch 'master' into nix-repl-flakes

src/libcmd/installables.cc

@@ -146,7 +146,8 @@ SourceExprCommand::SourceExprCommand(bool supportReadOnlyMode)
         .shortName = 'f',
         .description =
             "Interpret installables as attribute paths relative to the Nix expression stored in *file*. "
-            "If *file* is the character -, then a Nix expression will be read from standard input.",
+            "If *file* is the character -, then a Nix expression will be read from standard input. "
+            "Implies `--impure`.",
         .category = installablesCategory,
         .labels = {"file"},
         .handler = {&file},

src/libcmd/repl.cc

@@ -1066,6 +1066,11 @@ struct CmdRepl : InstallablesCommand
         return file.has_value() or expr.has_value();
     }
 
+    bool forceImpureByDefault() override
+    {
+        return true;
+    }
+
     std::string description() override
     {
         return "start an interactive environment for evaluating Nix expressions";