Replace string

Purpose: Replaces part of string.

 replace-string <string> \
     ( copy <replacement> ) | ( copy-end <replacement> ) \
     [ start-with <start with> ] \
     [ length <length> ]

replace-string will replace part of <string> with <replacement> string. "copy" clause will make a replacement in the leading part of <string>, while "copy-end" will make a replacement in the trailing part of <string>.

If "length" clause is not used, then the entire <replacement> string is used, otherwise only the <length> leading bytes of it.

If "start-with" clause is used, then <replacement> will be copied starting with byte <start with> in <string> ("0" being the first byte) (with "copy" clause) or starting with <start with> bytes prior to the end of <string> (with "copy-end" clause).

If "start-with" clause is not used, then <replacement> will replace the leading part of <string> (with "copy" clause") or the very last part of <string> (with "copy-end" clause). In either case, the number of bytes copied is determined by whether "length" clause is used or not.

If either "start-with" or "length" is negative, it's the same as if not specified.

Examples

After replace-string below, string "a" will be "none string is here":

 set-string b="none"
 set-string a="some string is here"
 replace-string a copy b

After replace-string below, string "a" will be "some string is none":

 set-string b="none"
 set-string a="some string is here"
 replace-string a copy-end b

In this example, "a" will be "somnontring is here":

 set-string b="none"
 set-string a="some string is here"
 replace-string a copy b start-with 3 length 3

In the following example, "a" will be "some string inohere":

 set-string b="none"
 set-string a="some string is here"
 replace-string a copy-end b start-with 6 length 2