replace_literal
Description:
public string replace_literal (string str, ssize_t string_len, int start_position, string replacement, RegexMatchFlags match_options = 0) throws RegexError
  
  Replaces all occurrences of the pattern in this with the replacement text.
 replacement is replaced literally, to include backreferences use 
        replace.
Setting start_position differs from just passing over a shortened string and setting 
        g_regex_match_notbol in the case of a pattern that begins with any kind of lookbehind assertion, such as "\b".
Example: Replace literal:
public int main (string[] args) {
	try {
		string str = "If I had some duck tape, I could fix that.";
		string old = "duck";
		string replacement = "duct";
		var regex = new GLib.Regex (GLib.Regex.escape_string (old));
		string result = regex.replace_literal (str, -1, 0, replacement);
		// Output:
		//  ``str: "If I had some duck tape, I could fix that."``
		//  ``old: "duck"``
		//  ``replacement: "duct"``
		//  ``result: "If I had some duct tape, I could fix that."``
		print ("str: \"%s\"\n", str);
		print ("old: \"%s\"\n", old);
		print ("replacement: \"%s\"\n", replacement);
		print ("result: \"%s\"\n", result);
	} catch (GLib.RegexError e) {
		GLib.assert_not_reached ();
	}
	return 0;
}
    
    valac --pkg glib-2.0 GLib.Regex.replace_literal.vala
    Parameters:
| this | 
           a Regex structure  | 
      
| string_len | 
           the length of   | 
      
| start_position | 
           starting index of the string to match, in bytes  | 
      
| replacement | 
           text to replace each match with  | 
      
| match_options | 
           options for the match  | 
      
| string | 
           the string to perform matches against  | 
      
Returns:
| 
           a newly allocated string containing the replacements  |