If the application invokes handler.nack() or allows handler to go out of scope, then the service will redeliver the message.
With exactly-once delivery subscriptions, the service will stop redelivering the message once the application invokes handler.ack() and the invocation succeeds. With best-efforts subscriptions, the service may redeliver the message, even after a successful handler.ack() invocation.
If handler is not an rvalue, you may need to use std::move(handler).ack() or std::move(handler).nack().
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-04-17 UTC."],[[["The latest version available is 2.37.0-rc, with previous versions ranging down to 2.11.0 for the `PullResponse` documentation."],["This documentation describes the response for a blocking pull in the context of Google Cloud Pub/Sub."],["Messages can be redelivered if the application invokes `handler.nack()` or the `handler` goes out of scope."],["The service behavior regarding message redelivery differs between exactly-once delivery and best-effort subscriptions, as specified in the google pub/sub documentation link."],["You might need to use `std::move(handler).ack()` or `std::move(handler).nack()` if the handler is not an rvalue."]]],[]]
