Value declaration

A value declaration binds a value to an identifier (which then works as a constant).

val id = exp;

where id is an CPN ML identifier and exp is a CPN ML expression, including multiset expressions. The expression represents the value to be associated with the identifier.

Value declarations expressions may use any value representation that is syntactically unique, without a prior color set declaration. These include: unit, bool, int, real, string, tuple, list, record.

val buffer_size = 10;

val string_val = “A string constant”;

val listVal = [1, 2, 5];

val tupleVal = (1, true, “abcd”);

Value declarations may use expressions of previously declared color sets.

val lastPacket = DATA(”####”);

The declaration of lastPacket would result in an error if a color set similar to the Packet color set had not been declared before lastPacket.

Multi-set and function expressions may be used as value specifiers.

val intMS = 1`2++2`8;

val add3 = fn x ⇒ x+3;