Ordinary constants declarations are no different from the Turbo Pascal or Delphi implementation.
The compiler must be able to evaluate the expression in a constant declaration at compile time. This means that most of the functions in the Run-Time library cannot be used in a constant declaration. Operators such as +, -, *, /, not, and, or, div(), mod(), ord(), chr(), sizeof can be used, however. For more information on expressions, chapter (
Constant declaration
)
You can only declare constants of the following types: Ordinal types,
Real types, Char, and String.
The following are all valid constant declarations:
Assigning a value to a constant is not permitted. Thus, given the previous
declaration, the following will result in a compiler error:
