Contract
Return type	wob
Parameter key	Default value	Type
item	req
same_case	true	boolean
start	0	integer
end	null
returns	"first"	string

Water Contract
<method string.key_of item =req same_case=true start =0 end =null returns ="first"/>

See also: key_of

key_of searches through _subject (a string) for a given substring. If substring is not in _subject then return false , else return the index of the first occurrence of substring within _subject

"abcde".<key_of "cd"/>

2

"abcde".<key_of "z"/>

false

Although the substring argument is usually a string, you may also pass in a character and the position of that character in _subject will be returned or false if not found. If substring is anything but a string or a char, false is returned because strings can only contain substrings or chars.