expression

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An expression is a non-productive rule that resolves by calculation into a value. They consist of at least one operand, and additional operands may be linked via non-unary operators. An operand may be

Examples of expressions are:

  • x + 5
  • 'Z'
  • response <> 42

Expressions, and parts thereof, can be classified by their result type. Usually primarily arithmetic and logic expressions are distinguished. An arithmetic expression results in a numeric value. A logic expression results in a Boolean value.

remarks

With compiler directive {$extendedSyntax on} a function call as an expression can appear as a statement, too. This is useful if the function triggers side-effects, but the return value is not needed.

see also