succ

#succ

##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
        else
            c := succ ( c )
        end if
    end for

##Details You cannot apply succ to the last value of an enumeration.

##See also the pred.html, lower.html and upper.html functions.