Properties and metadata

Call a method on its receiver

Indexes select stored values; metadata and methods describe how a value behaves. Receiver-first method syntax keeps the subject of an operation visible.

Runnable RiXRun cell

values := [1, 2]; newValues := values.Push(3); {: values, newValues };

The receiver values remains [1, 2]; Push returns [1, 2, 3] as a new value. The dot keeps the subject of the operation visible. See Arrays for more collection methods.

Know what a property means

Properties carry information about a value; methods compute or update from a receiver. Use .key when a stable object identity is needed. A method ending in ! signals a deliberate mutable operation; choose it only when shared state is part of the model. Cells and assignment explains that shared state.

Change the pushed value and confirm that the original array still has two items.

Continue with Shared ledger for a task involving values and aliases.