fix some failing tests

include/xlnt/utils/string.hpp

@@ -291,6 +291,9 @@ public:
 	friend std::ostream &operator<<(std::ostream &left, string &right);
 	friend string operator+(const char *left, const string &right);
 
+	friend bool operator==(const char *left, const string &right) { return right == left; }
+	friend bool operator!=(const char *left, const string &right) { return right != left; }
+
 private:
 	explicit string(size_type initial_size);
 

include/xlnt/workbook/workbook.hpp

@@ -174,6 +174,7 @@ class XLNT_CLASS workbook
     // named ranges
     std::vector<named_range> get_named_ranges() const;
     void create_named_range(const string &name, worksheet worksheet, const range_reference &reference);
+	void create_named_range(const string &name, worksheet worksheet, const string &reference_string);
     bool has_named_range(const string &name) const;
     range get_named_range(const string &name);
     void remove_named_range(const string &name);

include/xlnt/worksheet/range_reference.hpp

@@ -37,9 +37,9 @@ class XLNT_CLASS range_reference
     static range_reference make_absolute(const range_reference &relative_reference);
 
     range_reference();
-    range_reference(const string &range_string);
-    range_reference(const char *range_string);
-    range_reference(const std::pair<cell_reference, cell_reference> &reference_pair);
+    explicit range_reference(const string &range_string);
+    explicit range_reference(const char *range_string);
+    explicit range_reference(const std::pair<cell_reference, cell_reference> &reference_pair);
     range_reference(const cell_reference &start, const cell_reference &end);
     range_reference(column_t column_index_start, row_t row_index_start, column_t column_index_end, row_t row_index_end);
 
@@ -71,19 +71,24 @@ class XLNT_CLASS range_reference
     string to_string() const;
 
     bool operator==(const range_reference &comparand) const;
+
     bool operator==(const string &reference_string) const
     {
         return *this == range_reference(reference_string);
     }
+
     bool operator==(const char *reference_string) const
     {
         return *this == string(reference_string);
     }
+
     bool operator!=(const range_reference &comparand) const;
+
     bool operator!=(const string &reference_string) const
     {
         return *this != range_reference(reference_string);
     }
+
     bool operator!=(const char *reference_string) const
     {
         return *this != string(reference_string);

include/xlnt/worksheet/worksheet.hpp

@@ -292,6 +292,8 @@ class XLNT_CLASS worksheet
     const cell get_cell(const cell_reference &reference) const;
     range get_range(const range_reference &reference);
     const range get_range(const range_reference &reference) const;
+	range get_range(const string &reference_string);
+	const range get_range(const string &reference_string) const;
     range get_squared_range(column_t min_col, row_t min_row, column_t max_col, row_t max_row);
     const range get_squared_range(column_t min_col, row_t min_row, column_t max_col, row_t max_row) const;
     range rows() const;
@@ -341,8 +343,10 @@ class XLNT_CLASS worksheet
 
     // cell merge
     void merge_cells(const range_reference &reference);
+	void merge_cells(const string &reference_string);
     void merge_cells(column_t start_column, row_t start_row, column_t end_column, row_t end_row);
     void unmerge_cells(const range_reference &reference);
+	void unmerge_cells(const string &reference_string);
     void unmerge_cells(column_t start_column, row_t start_row, column_t end_column, row_t end_row);
     std::vector<range_reference> get_merged_ranges() const;
 
@@ -382,6 +386,7 @@ class XLNT_CLASS worksheet
     range_reference get_auto_filter() const;
     void auto_filter(const xlnt::range &range);
     void auto_filter(const range_reference &reference);
+	void auto_filter(const string &reference_string);
     void unset_auto_filter();
     bool has_auto_filter() const;
 

source/cell/cell.cpp

@@ -1071,7 +1071,7 @@ bool cell::has_hyperlink() const
 
 void cell::set_hyperlink(const string &hyperlink)
 {
-    if (hyperlink.length() == 0 || std::find(hyperlink.begin(), hyperlink.end(), ':') == hyperlink.end())
+    if (hyperlink.length() == 0 || hyperlink.find(':') == std::string::npos)
     {
         throw data_type_exception();
     }

source/serialization/tests/test_write_workbook.hpp

@@ -16,7 +16,7 @@ public:
         xlnt::workbook wb;
         auto ws = wb.create_sheet();
         ws.get_cell("F42").set_value("hello");
-        ws.get_auto_filter() = "A1:F1";
+        ws.auto_filter("A1:F1");
     
         xlnt::workbook_serializer serializer(wb);
         auto observed = serializer.write_workbook();

source/utils/string.cpp

@@ -540,22 +540,12 @@ void string::append(code_point c)
 
 string::code_point string::at(size_type index)
 {
-	auto iter = begin();
-	size_type i = 0;
-
-	while (i < index) ++iter;
-
-	return *iter;
+	return *(begin() + index);
 }
 
 const string::code_point string::at(size_type index) const
 {
-	auto iter = begin();
-	size_type i = 0;
-
-	while (i < index) ++iter;
-
-	return *iter;
+	return *(begin() + index);
 }
 
 bool string::operator==(const_byte_pointer str) const

source/workbook/workbook.cpp

@@ -924,4 +924,9 @@ void workbook::add_shared_string(const string &shared)
     d_->shared_strings_.push_back(shared);
 }
 
+void workbook::create_named_range(const string &name, worksheet owner, const string &reference_string)
+{
+	create_named_range(name, owner, range_reference(reference_string));
+}
+
 } // namespace xlnt

source/worksheet/worksheet.cpp

@@ -63,7 +63,7 @@ void worksheet::create_named_range(const string &name, const range_reference &re
 
 range worksheet::operator()(const xlnt::cell_reference &top_left, const xlnt::cell_reference &bottom_right)
 {
-    return get_range({ top_left, bottom_right });
+    return get_range(range_reference(top_left, bottom_right));
 }
 
 cell worksheet::operator[](const cell_reference &ref)
@@ -91,6 +91,26 @@ void worksheet::auto_filter(const range_reference &reference)
     d_->auto_filter_ = reference;
 }
 
+void worksheet::auto_filter(const string &reference_string)
+{
+	auto_filter(range_reference(reference_string));
+}
+
+void worksheet::merge_cells(const string &reference_string)
+{
+	merge_cells(range_reference(reference_string));
+}
+
+void worksheet::unmerge_cells(const string &reference_string)
+{
+	unmerge_cells(range_reference(reference_string));
+}
+
+range worksheet::get_range(const string &reference_string)
+{
+	return get_range(range_reference(reference_string));
+}
+
 void worksheet::auto_filter(const xlnt::range &range)
 {
     auto_filter(range.get_reference());