[JEXL-398] Allow 'trailing commas' or ellipsis while defining array, map and set literals

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.3
• Fix Version/s: 3.4.0
• Assignee: Henri Biestro
• Reporter: Xu Pengcheng
• Created: 25/Jun/23 00:29
• Updated: 23/Jan/24 10:52
• Resolved: 23/Jan/24 10:39

Description

Allowing trailing commas in structured literals (array, set, map) as a convenient syntactic leniency.

let m = { "foo": 1, "bar": 2, };
let a = [ 1, 2, ];
let s = (1, 2, );

Using a trailing ellipsis (...) to alter the concrete class materialized as a convenient semantic shortcut.

let m = { "foo": 1, "bar": 2, ... }; // LinkedHashMap
let a = [ 1, 2, ...]; // ArrayList
let s = (1, 2, ...); // LinkedHashSet