Substr   built-in function

The Substr function returns a substring of another string.

result = Substr( string, n [, [ length ] [, pad ] ] )

string

the original string

n

the position where the substring begins. A value of 1 indicates the first value in the string. When the position exceeds the length of the original string, then only pad characters are returned.

Caution: n must be positive ! If the value of n is computed, you should be sure that it is greater than 0. See the last two examples below.

length

the length of the substring to extract. When this argument is absent, the remainder of the string is returned. When the length exceeds the amount of characters remaining, padding characters are added at the end.

pad

an optional padding character, that is used at the end of the resulting substring. The default padding character is a space.

Examples: say Substr( 'abracadabra', 5 ) -- shows: cadabra say Substr( 'abracadabra', 5, 3 ) -- shows: cad say Substr( 'abracadabra', 7, 7, '+' ) -- shows: dabra++ say Substr( 'abracadabra', 99, 3, '+' ) -- shows: +++ str = '' pos = min( 1, length( str ) ) say Substr( str, pos, 3, '+' ) -- B-O-M-B-S ! .. pos is 0 ! say Substr( str, max( pos, 1 ), 3, '+' ) -- OK, shows nothing