Generate builtins section of the manual

1 files changed, 19 insertions, 1 deletions

diff --git a/src/nix/main.cc b/src/nix/main.cc
index 0c4fd46fd..210327927 100644
--- a/src/nix/main.cc
+++ b/src/nix/main.cc
@@ -179,11 +179,29 @@ void mainWrapped(int argc, char * * argv)
 
     NixArgs args;
 
-    if (argc == 2 && std::string(argv[1]) == "dump-args") {
+    if (argc == 2 && std::string(argv[1]) == "__dump-args") {
         std::cout << args.toJSON().dump() << "\n";
         return;
     }
 
+    if (argc == 2 && std::string(argv[1]) == "__dump-builtins") {
+        EvalState state({}, openStore("ssh://foo.invalid/"));
+        auto res = nlohmann::json::object();
+        auto builtins = state.baseEnv.values[0]->attrs;
+        for (auto & builtin : *builtins) {
+            auto b = nlohmann::json::object();
+            if (builtin.value->type != tPrimOp) continue;
+            auto primOp = builtin.value->primOp;
+            if (!primOp->doc) continue;
+            b["arity"] = primOp->arity;
+            b["args"] = primOp->args;
+            b["doc"] = trim(stripIndentation(primOp->doc));
+            res[(std::string) builtin.name] = std::move(b);
+        }
+        std::cout << res.dump() << "\n";
+        return;
+    }
+
     Finally printCompletions([&]()
     {
         if (completions) {