[GROOVY-10666] Implement multiple-assignment (aka destructuring) via getAt(IntRange) or iterator()

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 5.0.0-alpha-1
• Component/s: bytecode, groovy-jdk
• Assignee: Eric Milles
• Reporter: Eric Milles
• Created: 26/Jun/22 22:30
• Updated: 23/Aug/23 09:11
• Resolved: 10/Oct/22 08:15

Description

Currently multiple-assignment is implemented using getAt(int). For types that support getAt(IntRange) it may be more efficient to use that operation. For cases where getAt(int) is a terminal operation (aka streams) it may be the only way to go. Or maybe using one iterator() would be better overall.

Consider the following:

Set<String> set = ['foo','bar','baz']
def (foo, bar, baz) = set // inefficient; requires 3 iterators and 6 calls to next

Stream<String> stream = ['foo','bar','baz'].stream()
def (foo, bar, baz) = stream // not possible because `getAt(int)` is terminal

Issue Links

• is related to: GROOVY-5744 Multiple assignment from Iterator skips every other element
• is related to: GROOVY-10473 Extend streams support to spread and subscript