subrangetype

#subrangeType

##Syntax A subrangeType is:

expn .. expn

##Description A subrange type defines a set of values, for example, the subrange 1 .. 4 consists of 1, 2, 3 and 4.

##Example

    var i : 1 .. 10         % i can be 1, 2 � up to 10
    type xRange : 0 .. 319      % Define integer subrange
    var pixels : array xRange of int
                        % Array elements are
                        % numbered 0, 1, � 319
    for k : xRange          % k ranges from 0 to 319
        pixels ( k ) := 0
    end for

##Details A subrange must contain at least one element. In other words, the second expression (expn) must be at least as large as the first expression.

The lower bound of a subrange must be known at compile time. The upper bound is allowed to be a run time value only in one situation and that is when it gives the upper bound of an array being declared in a variable declaration, in other words when declaring a dynamic array.

Subranges are usually a subset of the integers, as in 1 .. 10. You can also have subranges of enumerated types and characters (the char type).

You can apply lower and upper to subrange types.