diff --git a/src/metta.pl b/src/metta.pl
index a00724e..9f74692 100644
--- a/src/metta.pl
+++ b/src/metta.pl
@@ -267,6 +267,7 @@
 %%% Registration: %%%
 :- dynamic fun/1.
 register_fun(N) :- (fun(N) -> true ; assertz(fun(N))).
+argv(K, Arg) :- current_prolog_flag(argv, Argv), nth0(K, Argv, Arg).
 
 :- maplist(register_fun, [superpose, empty, let, 'let*', '+','-','*','/', '%', min, max, 'change-state!', 'get-state', 'bind!',
                           '<','>','==', '!=', '=', '=?', '<=', '>=', and, or, xor, implies, not, sqrt, exp, log, cos, sin,
@@ -282,4 +283,4 @@
                           'acos-math', 'atan-math', 'isnan-math', 'isinf-math', 'min-atom', 'max-atom',
                           'foldl-atom', 'map-atom', 'filter-atom','current-time','format-time', library, exists_file,
                           import_prolog_function, 'Predicate', callPredicate, assertaPredicate, assertzPredicate, retractPredicate,
-                          'add-translator-rule!', 'remove-translator-rule!']).
+                          'add-translator-rule!', 'remove-translator-rule!', argv]).