The length conversion code performs string length constraint checks. It works identically on input and output conversions and has three forms:
L | Returns the length of the string being converted. |
Ln | Returns the original string if its length is less than or equal to n. Otherwise it returns a null string. |
Ln,m | Returns the original string if its length is greater than or equal to n and less than or equal to m. Otherwise it returns a null string. |
Examples
Conversion
|
Data
|
Result
|
L
|
1234
|
4
|
L3
|
A
|
A
|
L3
|
AB
|
AB
|
L3
|
ABC
|
ABC
|
L3
|
ABCD
|
|
L2,3
|
A
|
|
L2,3
|
AB
|
AB
|
L2,3
|
ABC
|
ABC
|
L2,3
|
ABCD
|
|
|