Added <,>,<= and >= operators functions for strings.

3 files changed, 45 insertions, 0 deletions

diff --git a/include/string b/include/string
index e7fe904..dccd5ac 100644
--- a/include/string
+++ b/include/string
@@ -306,6 +306,15 @@ class string
     size_type mLength;  // len of the string excl. null-terminator.
 };
 
+// Comparaison:
+bool operator<(const string& lhs, const string& rhs);
+bool operator<=(const string& lhs, const string& rhs);
+bool operator>(const string& lhs, const string& rhs);
+bool operator>=(const string& lhs, const string& rhs);
+
+// Swap
+void swap(string& lhs, string& rhs);
+
 // I/O
 ostream& operator<<(ostream& os, const string& str);
 
diff --git a/src/string.cpp b/src/string.cpp
index 4e763e6..d2457fc 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -613,6 +613,26 @@ string::size_type string::find_last_not_of(value_type c, size_type pos) const {
     }
 }
 
+bool operator<(const string& lhs, const string& rhs) {
+    return lhs.compare(rhs) < 0;
+}
+
+bool operator<=(const string& lhs, const string& rhs) {
+    return lhs.compare(rhs) <= 0;
+}
+
+bool operator>(const string& lhs, const string& rhs) {
+    return lhs.compare(rhs) > 0;
+}
+
+bool operator>=(const string& lhs, const string& rhs) {
+    return lhs.compare(rhs) >= 0;
+}
+
+void swap(string& lhs, string& rhs) {
+    lhs.swap(rhs);
+}
+
 ostream& operator<<(ostream& os, const string& str) {
     return os.write_formatted(str.data(), str.size());
 }
diff --git a/tests/test_string.cpp b/tests/test_string.cpp
index 412f065..c2405ae 100644
--- a/tests/test_string.cpp
+++ b/tests/test_string.cpp
@@ -488,6 +488,22 @@ bool testCompare()
 
     string str06;
     EXPECT_TRUE(str06 != NULL);
+    {
+        string str_long("this is");
+        string str_short("it");
+        EXPECT_TRUE(str_long > str_short);
+        EXPECT_TRUE(str_long >= str_short);
+        EXPECT_FALSE(str_long < str_short);
+        EXPECT_FALSE(str_long <= str_short);
+    }
+    {
+        string str_lhs("this is");
+        string str_rhs("this is");
+        EXPECT_FALSE(str_lhs > str_rhs);
+        EXPECT_TRUE(str_lhs >= str_rhs);
+        EXPECT_FALSE(str_lhs < str_rhs);
+        EXPECT_TRUE(str_lhs <= str_rhs);
+    }
     return true;
 }