Skip to main content
Version: 7.0

[] operator

The [] operator creates a property that returns an object from a structure.

Syntax​

expr[n]

Where [ and ] are ordinary square brackets.

Description​

The [] operator creates a property that takes a structure as input and returns the structure object at the position given by n.

Parameters​

  • expr

    An expression whose value must be a structure.

  • n

    The position of the object within the structure. A positive integer literal: it must be written as a constant, not computed from an expression. Numbering is 1-based, and the value must be within the range [1..N], where N is the number of objects in the structure.

Examples​

CLASS Letter;
attachment1 = DATA FILE (Letter);
attachment2 = DATA FILE (Letter);
letterAttachments (Letter l) = STRUCT(attachment1(l), attachment2(l));
secondAttachment(Letter l) = letterAttachments(l)[2]; // returns attachment2