substring
extracts a portion of a string
(string subject, long start, long end) -> string
Returns a substring of subject
beginning at index start
(inclusive) up to index end
(exclusive). If end
is nil
, the substring extends to the end of subject
.
Returns nil
if subject is nil
.
Returns an empty string if end <= start
.
Throws an error if start
is nil
or start < 0
.
Parameters
Name | Type | Description |
---|---|---|
subject |
string | The string to split |
start |
long |
The index of the first character that should be in the result. Indexes are zero-based, i.e. the first character is at index 0. |
end |
long |
The index of the first character to not include in the result. Indexes are zero-based, i.e. the first character is at index 0. If |