Documentation for infix = (list assignment) assembled from the following pages:

Language documentation: Operators §

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(Operators) infix = (list assignment) §

The list assignment operator generally copies values from its right-hand side into the container on its left-hand side. Its exact semantics are left to the left-hand side container type. See Array and Hash for common cases.

The list assignment operator should be distinguished from the item assignment operator, which uses the same operator symbol = but has a higher precedence. The context of the left-hand side of the = symbol determines whether it is parsed as item assignment or list assignment. See the section on item and list assignment for a comparative discussion of the two assignment types.