Use a templated find() to enable lookup without object creation when objects are comparable.

4 files changed, 40 insertions, 7 deletions

diff --git a/vespalib/src/tests/stllike/hash_test.cpp b/vespalib/src/tests/stllike/hash_test.cpp
index e7fe729c1ba..4feeaef8349 100644
--- a/vespalib/src/tests/stllike/hash_test.cpp
+++ b/vespalib/src/tests/stllike/hash_test.cpp
@@ -154,14 +154,14 @@ TEST("test hash set with simple type")
 
 TEST("test hash map iterator stability")
 {
-    hash_map<int, int> h;
+    hash_map<uint32_t, uint32_t> h;
     EXPECT_EQUAL(1ul, h.capacity());
     for (size_t i(0); i < 100; i++) {
         EXPECT_TRUE(h.find(i) == h.end());
         h[i] = i;
         EXPECT_TRUE(h.find(i) != h.end());
-        int * p1 = & h.find(i)->second;
-        int * p2 = & h[i];
+        uint32_t * p1 = & h.find(i)->second;
+        uint32_t * p2 = & h[i];
         EXPECT_EQUAL(p1, p2);
     }
     EXPECT_EQUAL(128ul, h.capacity());
diff --git a/vespalib/src/vespa/vespalib/stllike/hash_fun.h b/vespalib/src/vespa/vespalib/stllike/hash_fun.h
index f708f49081e..de849b8924e 100644
--- a/vespalib/src/vespa/vespalib/stllike/hash_fun.h
+++ b/vespalib/src/vespa/vespalib/stllike/hash_fun.h
@@ -6,6 +6,20 @@
 
 namespace vespalib {
 
+template<typename T, typename F>
+struct cast_static {
+    T operator() (const F & o) const {
+        return static_cast<T>(o);
+    }
+};
+
+template<typename L, typename R>
+struct equal_to : public std::binary_function<L, R, bool>
+{
+    bool operator()(const L & __x, const R & __y) const { return __x == __y; }
+    bool operator()(const R & __x, const L & __y) const { return __x == __y; }
+};
+
 template<typename K> struct hash {
     // specializations operate as functor for known key types
     size_t operator() (const K & v) const {
diff --git a/vespalib/src/vespa/vespalib/stllike/hash_map.h b/vespalib/src/vespa/vespalib/stllike/hash_map.h
index 6d6498f8e78..929a3740a1d 100644
--- a/vespalib/src/vespa/vespalib/stllike/hash_map.h
+++ b/vespalib/src/vespa/vespalib/stllike/hash_map.h
@@ -50,6 +50,25 @@ public:
     void erase(const_iterator it)               { return erase(it->first); }
     iterator find(const K & key)                { return _ht.find(key); }
     const_iterator find(const K & key)    const { return _ht.find(key); }
+
+    template< typename AltKey, typename AltExtract=std::_Identity<K>, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
+    const_iterator find(const AltKey & key) const {
+        return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key);
+    }
+    template< typename AltKey, typename AltExtract=std::_Identity<K>, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
+    iterator find(const AltKey & key) {
+        return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key);
+    }
+    template< typename AltKey, typename AltExtract, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
+    const_iterator find(const AltKey & key, const AltExtract & altExtract) const {
+        return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key, altExtract);
+    }
+
+    template< typename AltKey, typename AltExtract, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
+    iterator find(const AltKey & key, const AltExtract & altExtract) {
+        return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key, altExtract);
+    }
+
     void clear();
     void resize(size_t newSize);
     void swap(hash_map & rhs);
diff --git a/vespalib/src/vespa/vespalib/stllike/hash_set.h b/vespalib/src/vespa/vespalib/stllike/hash_set.h
index c4ccc662787..9756a3083df 100644
--- a/vespalib/src/vespa/vespalib/stllike/hash_set.h
+++ b/vespalib/src/vespa/vespalib/stllike/hash_set.h
@@ -48,18 +48,18 @@ public:
     template <typename Func>
     void for_each(Func func) const { _ht.for_each(func); }
 
-    template< typename AltKey, typename AltExtract, typename AltHash, typename AltEqual >
+    template< typename AltKey, typename AltExtract=std::_Identity<K>, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
     const_iterator find(const AltKey & key) const { return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key); }
 
-    template< typename AltKey, typename AltExtract, typename AltHash, typename AltEqual >
+    template< typename AltKey, typename AltExtract=std::_Identity<K>, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
     iterator find(const AltKey & key) { return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key); }
 
-    template< typename AltKey, typename AltExtract, typename AltHash, typename AltEqual >
+    template< typename AltKey, typename AltExtract, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
     const_iterator find(const AltKey & key, const AltExtract & altExtract) const {
         return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key, altExtract);
     }
 
-    template< typename AltKey, typename AltExtract, typename AltHash, typename AltEqual >
+    template< typename AltKey, typename AltExtract, typename AltHash=vespalib::hash<AltKey>, typename AltEqual=equal_to<AltKey, K> >
     iterator find(const AltKey & key, const AltExtract & altExtract) {
         return _ht.template find<AltKey, AltExtract, AltHash, AltEqual>(key, altExtract);
     }