(substr string start [length])
Give me part of that string.
This function takes apart strings. It takes out a sub-string from the original string, which you can then assign to a variable or use as any other string.
The argument start indicates which character in the string to start from. Unlike other functions that deal with elements of a list, substr considers the first character in the string as number one (not #0). When the start position is greater than the length of the string, substr returns "" (non-nil).
The length argument represents the number of characters to include in the sub-string; this value must be a positive integer. If this argument is not provided, the sub-string extends to the end of the original string. When the integer is larger than the number of characters available, the entire list from the specified first character to the end will be returned with no error.
Examples
Code | Returns |
---|---|
(substr "California" 4 3 ) | "ifo" |
(substr "Texas" 3 ) | "xas" |
(substr "New Mexico" 12 ) | "" |