The brackets operator extracts a substring from a string, or assigns a substring to a string. Which action is taken depends upon the syntax.
Throughout this manual, optional parameters in syntax are enclosed in brackets. This usage differs from using brackets as an operator, which is described in this topic. For more information on typographical conventions used in this manual, refer to Typographical Conventions.
See Also
Using the Brackets Operator for Insertion, Using the Brackets Operator for Extraction
