Difference between revisions of "Language Reference/Constants"
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Revision as of 10:55, 5 November 2008
Constants Sections
A constants section defines a set of constants in the current scope.
ConstantsSection : constants ConstantDefinition-dot-term-list-opt
Constant Definitions
A constant definition defines a named constant, its type, and its value.
ConstantDefinition: one of ConstantName = ConstantValue ConstantName : TypeName = ConstantValue
ConstantName: LowerCaseIdentifier
The ConstantValue should be an expression, which can be evaluated at compile time and it should have the type of the correspondent domain. The ConstantName should be a lower case identifier.
The TypeName can be omitted only for the following built-in domains:
- Numerical (i.e. integral or real) constants. In this case, the corresponding anonymous numerical domain is adopted for a constant (see the numerical domains for details).
- Binary constants.
- String constants.
- Character constants.
Example
constants my_char = 'a'. true_const : boolean = true. binaryFileName = "mybin". myBinary = #bininclude(binaryFileName).