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Expressions


Expressions appear in many places and compute a function of one or more variables. Expressions are built from data object references and built in operators. The rules for building expressions are:
qualified-expression : type "'" "(" expression ")"
expression : relation { AND relation } |
    relation { OR relation } |
    relation { XOR relation } |
    relation [ NAND relation ] |
    relation [ NOR relation ]
relation : simple-expression [ relational-operator simple-expression ]
simple-expression : [ sign ] term { adding-operator term }
term : factor { multiplying-operator factor }
factor : primary [ ** primary ] |
    ABS primary |
    NOT primary
primary : name | literal | aggregate | function-call |
    qualified-expression | allocator | "(" expression ")"

This section is divided into two parts that describe first how data objects may be referenced and second what operators are available for different types.

Using data objects
Operators