added to Space: long double to Space::Value and methods for converting from/to long double

added global methods for converting float/string double/string and long double/string (convert/double.h|cpp):
      float to_float(const char * str, const char ** after = nullptr);
      float to_float(const wchar_t * str, const wchar_t ** after = nullptr);
      double to_double(const char * str, const char ** after = nullptr);
      double to_double(const wchar_t * str, const wchar_t ** after = nullptr);
      long double to_long_double(const char * str, const char ** after = nullptr);
      long double to_long_double(const wchar_t * str, const wchar_t ** after = nullptr);
      float to_float(const std::string & str, const char ** after = nullptr);
      float to_float(const std::wstring & str, const wchar_t ** after = nullptr);
      double to_double(const std::string & str, const char ** after = nullptr);
      double to_double(const std::wstring & str, const wchar_t ** after = nullptr);
      long double to_long_double(const std::string & str, const char ** after = nullptr);
      long double to_long_double(const std::wstring & str, const wchar_t ** after = nullptr);
      std::string to_str(float val);
      std::wstring to_wstr(float val);
      std::string to_str(double val);
      std::wstring to_wstr(double val);
      std::string to_str(long double val);
      std::wstring to_wstr(long double val);

src/textstream/textstream.h

@@ -124,6 +124,10 @@ public:
 	TextStreamBase & operator<<(const Space & space);
 	TextStreamBase & operator<<(const Date & date);
 
+	char get_char(size_t index) const;
+	wchar_t get_wchar(size_t index) const;
+
+
 	// min width for integer output
 	// if the output value has less digits then first zeroes are added
 	// (0 turn off)
@@ -518,7 +522,7 @@ TextStreamBase<char_type, stack_size, heap_block_size>::operator<<(double v)
 {
 char buf[100];
 
-	snprintf(buf, sizeof(buf)/sizeof(char), "%f", v);
+	snprintf(buf, sizeof(buf)/sizeof(char), "%g", v);
 	return operator<<(buf);
 }
 
@@ -529,7 +533,7 @@ TextStreamBase<char_type, stack_size, heap_block_size>::operator<<(long double v
 {
 char buf[100];
 
-	snprintf(buf, sizeof(buf)/sizeof(char), "%Lf", v);
+	snprintf(buf, sizeof(buf)/sizeof(char), "%Lg", v);
 	return operator<<(buf);
 }
 
@@ -635,6 +639,21 @@ return *this;
 }
 
 
+template<typename char_type, size_t stack_size, size_t heap_block_size>
+char TextStreamBase<char_type, stack_size, heap_block_size>::get_char(size_t index) const
+{
+	return static_cast<char>(buffer[index]);
+}
+
+
+template<typename char_type, size_t stack_size, size_t heap_block_size>
+wchar_t TextStreamBase<char_type, stack_size, heap_block_size>::get_wchar(size_t index) const
+{
+	return static_cast<wchar_t>(buffer[index]);
+}
+
+
+
 
 template<typename char_type, size_t stack_size, size_t heap_block_size>
 template<typename arg_char_type, size_t arg_stack_size, size_t arg_heap_block_size>