succsuccessor function

Syntax   succ ( expn )

Description   The succ function accepts an integer, character or an enumerated value and returns the integer plus one, the next character, or the next value in the enumeration. For example, succ (7) is 8.

Example   This part of a Turing program fills up array a with the enumerated values green, yellow, red, green, yellow, red, etc.

        type colors : enum ( green, yellow, red  )
        var a : array 1 .. 100 of colors
        var c : colors := colors .green
        for i : 1 .. 100
            a ( i ) := c
            if c = colors . red then
                c := colors . green
                c := succ ( c )
            end if
        end for
Details   You cannot apply succ to the last value of an enumeration.

See also   the pred, lower and upper functions.