From 33278ed54578b3e110f22f8e97a3687a81df811e Mon Sep 17 00:00:00 2001
From: Cotton Seed <cotton@alum.mit.edu>
Date: Thu, 29 Dec 2011 11:51:58 -0500
Subject: [PATCH] Added hash and comparisons for std::string.

---
 lib/lib.cpp | 10 ++++++++++
 lib/lib.h   | 17 +++++++++++++++++
 main.cpp    | 20 +++++++++++++++++++-
 3 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/lib/lib.cpp b/lib/lib.cpp
index 74ff094..45f700c 100644
--- a/lib/lib.cpp
+++ b/lib/lib.cpp
@@ -72,3 +72,13 @@ alpha_to_int (char c)
       return - (c - 'A' + 1);
     }
 }
+
+hash_t 
+hash (const std::string &s)
+{
+  size_t n = s.length ();
+  hash_t h = hash (n);
+  for (unsigned i = 0; i < n; i ++)
+    h = hash_combine (h, hash (s[i]));
+  return h;
+}
diff --git a/lib/lib.h b/lib/lib.h
index 3c97fbf..e72b113 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -47,6 +47,23 @@ inline hash_t hash (unsigned long x) { return (hash_t)x; }
 
 inline hash_t hash (uint64 x) { return (hash_t)((x >> 32) ^ x); }
 
+hash_t hash (const std::string &s);
+
+inline bool operator == (const std::string &s, const std::string &t)
+{
+  return strcmp (s.c_str (), t.c_str ()) == 0;
+}
+
+inline bool operator < (const std::string &s, const std::string &t)
+{
+  return strcmp (s.c_str (), t.c_str ()) < 0;
+}
+
+inline bool operator <= (const std::string &s, const std::string &t)
+{
+  return strcmp (s.c_str (), t.c_str ()) <= 0;
+}
+
 template<class T>
 inline hash_t hash (const T &x)
 {
diff --git a/main.cpp b/main.cpp
index 7aec9c6..5c7a627 100644
--- a/main.cpp
+++ b/main.cpp
@@ -143,7 +143,25 @@ main ()
   }
 #endif
   
-#if 1
+  map<std::string, int> m;
+  m.push ("foo", 3);
+  m.push ("barz", 4);
+  m.push ("pazazz", 39);
+  
+  assert (m % "foo");
+  assert (m("foo") == 3);
+  assert (! (m % "fop"));
+  
+  hashmap<std::string, int> m2;
+  m2.push ("foo", 3);
+  m2.push ("barz", 4);
+  m2.push ("pazazz", 39);
+  
+  assert (m2 % "foo");
+  assert (m2("foo") == 3);
+  assert (! (m2 % "fop"));
+  
+#if 0
   test_ring<Z2> (2);
   test_ring<Z> (0);
   test_ring<Q> (0);