SETREPLACE - Replace a substring with another substring

Syntax:	SETREPLACE	[ variable ] = [ source ] [ old substring ] [ new substring ]
Arguments:	[ variable ]	Variable to assign; if the variable does not previously exist it is created.
	[ source ]	Variable or string containing the full original source string.
	[ old substring ]	Variable or string defining the substring to be replaced.
	[ new substring ]	Variable or string defining the replacement value.
Options:	/ignorecase	Ignore character case in source string when scanning for matching substrings.

This script command scans the [ source ] string and replaces all instances of the [ old substring ] with [ new substring ] and saves the result in [ variable ].

The resulting mine variable contains the value "This is my string.". The original string variable is unchanged.