When this extension is enabled (the default), the Irie Pascal compiler will recognize constant ranges in case statements and variant records.
You can use constant ranges to specify a number of consecutive case constants. To use a constant range you specify the first constant, and the last constant, separated by .. as follows:
first..last
So for example you could use the constant range
1..5
to specify the following constants
1, 2, 3, 4, 5
See the Irie Pascal Programmer's Reference Manual (in "progref.html") for more information.