SYNOPSIS
	string extract(string str, int from, int to)
	string extract(string str, int from)
	string str[from .. to]

DESCRIPTION
	Extract a substring from a string. Character 0 is first character.
	
	extract(str, n) will return a substring from characer number n
	to the end of str.
	
	extract(str, i, j) will return a string from character i to
	character j.
	
	The expression str[from .. to] is equivalent to extract(str,
	from, to).
	
	If you use extract(), then from and to may be given as negative
	integers to indicate positions from the end of the string. If you
	use the str[] form, you have to prepend the number with a < sign
	(see examples).

	Warning: the extract() is supported only for hysterical
	raisins. Use the [..] notation instead.

EXAMPLES
	str="this is a test";
	extract(str,4,4)   <=> str[4..4]   : " "	NOTE: str[4] == 32
	extract(str,4,7)   <=> str[4..7]   : " is "
	extract(str,-5)	   <=> str[<5..<1] : " test"
	extract(str,-5,-2) <=> str[<5..<2] : " tes"
	extract(str,2,-3)  <=> str[2..<3]  : "is is a te"
	extract(str,500),extract(str,-500),str[8..<8] : ""

SEE ALSO
	sscanf(E), explode(E)