add limits when parsing a json/space format

while here:
- add column index error
- add parsing methods with pt::TextStream and pt::WTextStream arguments

src/convert/baseparser.h

@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (c) 2021, Tomasz Sowa
+ * Copyright (c) 2021-2022, Tomasz Sowa
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -54,6 +54,7 @@ protected:
 
 	virtual void clear_input_flags();
 
+	virtual void check_new_line();
 	virtual int read_utf8_char();
 	virtual int read_ascii_char();
 	virtual int read_char_from_wchar_string();
@@ -72,6 +73,11 @@ protected:
 	*/
 	int line;
 
+	/*
+		a number of a column in which there is a syntax_error
+	*/
+	int column;
+
 
 	/*
 		true if parse() method was called