$Lstr_Substr
Substring of a longstring
Note: Many $functions have been deprecated in favor of Object Oriented methods. The OO equivalent for the $Lstr_Substr function is Substring.
This function takes a string or longstring input and produces a substring of the input, possibly padded to an indicated length.
The $Lstr_Substr function accepts four arguments and returns a string result.
The first argument is an arbitrary string or longstring. This is a required argument.
The second argument is a number between 1 and 2**31-1 that indicates the starting character in the input string. This is a required argument.
The third argument is a number between 1 and 2**31-1 that indicates the length of the result string. This is an optional argument and defaults to the number of characters in the input string starting at the position indicated by the second argument.
The fourth argument is a string containing a single character to be used as the pad character if the result length is longer than the string specified by argument one. This is an optional argument and defaults to a blank.
Syntax
%result = $Lstr_Substr(longstring, start, len, pad)
%result is a substring of the input longstring, padded with the pad character if necessary.
Usage notes
- $Lstr_Substr acts very much like $SUBSTR except:
- It pads the result to the length indicated by the third argument if the third argument is specified.
- It has a fourth pad character argument.
- It cancels the request if the result target is too short to hold the result.
- It cancels the request if the pad character argument is longer than one byte.
- It can operate on LONGSTRING inputs.
- It produces a LONGSTRING output.
Examples
- To set %BIG to
find:%BIG = $Lstr_Substr('Gryffindor', 5, 4)
- To set %BIG to
infollowed by 298 asterisks:%BIG = $Lstr_Substr('Slytherin', 8, 300, '*')