1 files changed, 56 insertions, 0 deletions
diff --git a/libbuild2/functions-builtin.cxx b/libbuild2/functions-builtin.cxx
new file mode 100644
index 0000000..44ae534
--- /dev/null
+++ b/libbuild2/functions-builtin.cxx
@@ -0,0 +1,56 @@
+// file      : libbuild2/functions-builtin.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbuild2/function.hxx>
+#include <libbuild2/variable.hxx>
+
+namespace build2
+{
+  // Return NULL value if an environment variable is not set, untyped value
+  // otherwise.
+  //
+  static inline value
+  getenvvar (const string& name)
+  {
+    optional<string> v (getenv (name));
+
+    if (!v)
+      return value ();
+
+    names r;
+    r.emplace_back (to_name (move (*v)));
+    return value (move (r));
+  }
+
+  void
+  builtin_functions ()
+  {
+    function_family f ("builtin");
+
+    f["type"] = [](value* v) {return v->type != nullptr ? v->type->name : "";};
+
+    f["null"]  = [](value* v) {return v->null;};
+    f["empty"] = [](value* v)  {return v->null || v->empty ();};
+
+    f["identity"] = [](value* v) {return move (*v);};
+
+    // string
+    //
+    f["string"] = [](bool b) {return b ? "true" : "false";};
+    f["string"] = [](uint64_t i) {return to_string (i);};
+    f["string"] = [](name n) {return to_string (n);};
+
+    // getenv
+    //
+    f["getenv"] = [](string name)
+    {
+      return getenvvar (name);
+    };
+
+    f["getenv"] = [](names name)
+    {
+      return getenvvar (convert<string> (move (name)));
+    };
+  }
+}