Task

Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.

Note: The order of the middle digits should be preserved.

Your function should be tested with the following values; the first line should return valid answers, those of the second line should return clear indications of an error:

123, 12345, 1234567, 987654321, 10001, -10001, -123, -100, 100, -12345
1, 2, -1, -10, 2002, -2002, 0

Show your output on this page.




fcn middle(ns){
   ns.apply("toString").apply('-("-"))
   .apply(fcn(n){nl:=n.len(); 
      if(nl<3 or nl.isEven) return(False);
      n[(nl-3)/2,3] : "%03d".fmt(_)
   })
}
middle(T(123,12345,1234567,987654321,10001,-10001,-123,-100,100,-12345)).println()
middle(T(1, 2, -1, -10, 2002, -2002, 0)).println();