diff --git a/include/r3.h b/include/r3.h
index e6ba33a..2a75460 100644
--- a/include/r3.h
+++ b/include/r3.h
@@ -174,6 +174,8 @@ route * r3_tree_match_route(const node *n, match_entry * entry);
 #define METHOD_HEAD 2<<5
 #define METHOD_OPTIONS 2<<6
 
-enum { OP_EXPECT_DIGITS, OP_EXPECT_WORDS, OP_EXPECT_NOSLASH };
+int r3_pattern_to_opcode(char * pattern, int pattern_len);
+
+enum { OP_EXPECT_DIGITS = 1, OP_EXPECT_WORDS, OP_EXPECT_NOSLASH };
 
 #endif /* !R3_NODE_H */
diff --git a/src/str.c b/src/str.c
index a02da74..1d63873 100644
--- a/src/str.c
+++ b/src/str.c
@@ -13,6 +13,20 @@
 #include "str_array.h"
 #include "zmalloc.h"
 
+int r3_pattern_to_opcode(char * pattern, int pattern_len) {
+    if ( strncmp(pattern, "\\w+", pattern_len) == 0 ) {
+        return OP_EXPECT_WORDS;
+    }
+    if ( strncmp(pattern, "\\d+", pattern_len) == 0 ) {
+        return OP_EXPECT_DIGITS;
+    }
+    if ( strncmp(pattern, "[^/]+", pattern_len) == 0 ) {
+        return OP_EXPECT_NOSLASH;
+    }
+    return 0;
+}
+
+
 
 /**
  * provide a quick way to count slugs, simply search for '{'
diff --git a/tests/check_slug.c b/tests/check_slug.c
index 1453fd2..6acb7fa 100644
--- a/tests/check_slug.c
+++ b/tests/check_slug.c
@@ -13,6 +13,14 @@
 #include "str_array.h"
 #include "zmalloc.h"
 
+START_TEST (test_pattern_to_opcode)
+{
+    ck_assert( r3_pattern_to_opcode("\\w+", sizeof("\\w+") - 1) == OP_EXPECT_WORDS );
+    ck_assert( r3_pattern_to_opcode("\\d+", sizeof("\\d+") - 1) == OP_EXPECT_DIGITS );
+    ck_assert( r3_pattern_to_opcode("[^/]+", sizeof("[^/]+") - 1) == OP_EXPECT_NOSLASH );
+}
+END_TEST
+
 START_TEST (test_slug_compile)
 {
     char * path = "/user/{id}";
@@ -106,6 +114,7 @@ Suite* r3_suite (void) {
         tcase_add_test(tcase, test_find_slug_placeholder_with_broken_slug);
         tcase_add_test(tcase, test_slug_count);
         tcase_add_test(tcase, test_slug_compile);
+        tcase_add_test(tcase, test_pattern_to_opcode);
 
         suite_add_tcase(suite, tcase);
         return suite;