Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

lib: faster event listening #41309

Closed
wants to merge 2 commits into from
Closed

lib: faster event listening #41309

wants to merge 2 commits into from

Commits on Dec 24, 2021

  1. lib: faster event listening 

    The current EventEmitter uses arrays to control multiple listeners,
but that means that prependListener and removeListeners operations
have an O(N) time complexity. With this change, instead of an array
we use a map + a linked list (to preserve execution order), which
gives an O(1) time complexity for those operations. This will be
especially helpful in scenarios where we have many listeners to
the same event.

BREAKING CHANGE: I don't know how much this is a breaking change,
because if someone is using the _events property, I think it is bad
usage that has no guarantees to keep working. Regardless, the _events
property will no longer be a function or an array, but a function
or a "MappedLinkedList". Some of the operations from the array are
present, though, like [Symbol.iterator], unshift and push, making
it possible to adapt some code that is arbritary using it
    @Farenheith
    Farenheith committed Dec 24, 2021
    Configuration menu
    Copy the full SHA
    eb49f16 View commit details
    Browse the repository at this point in the history

  2. lib: changing shift to pop during remove method 

    To make sure the removing of method follows a LIFO logic
when the same listener is added twice, it's important to
do a pop instead of a shift operation
    @Farenheith
    Farenheith committed Dec 24, 2021
    Configuration menu
    Copy the full SHA
    9b769a3 View commit details
    Browse the repository at this point in the history