Re: RFC: Add `final class Vector` to PHP

Hello Tyson, Vector support would be very good. JIT can do a lot with them if we have a clean Vector implementation, or even without JIT. What is your base inspiration for Vector? I do like the pretty standard C++ Vector implementation: https://www.cplusplus.com/reference/vector/vector/ Where a Vector is initalizied with: $myIntVector = vector<Integer>; What is key for performance is also the alloc/realloc/free strategy. In C++ (or most C or other languages custom) gives control to the creators to define max size, capacity, etc. If a non typed Vector is the goal, then I am less in need of it, still good to have but not as good as a clear pure Vector support :). Also I think it will be very good to have more details about what this RFC proposes in the RFC. It is kind of hard to follow right now, with all external links. RFCs are better if they act as a real specification :) Best, Pierre On Fri, Sep 17, 2021 at 9:10 AM tyson andre <tysonandre775@hotmail.com> wrote: > > Hi internals, > > I've created a new RFC https://wiki.php.net/rfc/vector > proposing to add final class Vector to PHP. > > PHP's native array type is rare among programming language > in that it is used as an associative map of values, but also needs to support lists of values. > In order to support both use cases while also providing a consistent internal array HashTable > API to the PHP's internals and PECLs, additional memory is needed to track keys > (https://www.npopov.com/2014/12/22/PHPs-new-hashtable-implementation.html - around twice as much as > is needed to just store the values due to needing space both for the string pointer and int key in a > Bucket, for non-reference counted values)). > Additionally, creating non-constant arrays will allocate space for at least 8 elements to make > the initial resizing more efficient, potentially wasting memory. > > It would be useful to have an efficient variable-length container in the standard library for > the following reasons: > > 1. To save memory in applications or libraries that may need to store many lists of values > and/or run as a CLI or embedded process for long periods of time > (in modules identified as using the most memory or potentially exceeding memory limits in > the worst case) > (both in userland and in native code written in php-src/PECLs) > 2. To provide a better alternative to ArrayObject and > SplFixedArray for use cases > where objects are easier to use than arrays - e.g. variable sized collections (For lists of > values) that can be passed by value to be read and modified. > 3. To give users the option of stronger runtime guarantees that property, parameter, or return > values really contain a list of values without gaps, that array modifications don't introduce > gaps or unexpected indexes, etc. > > Thoughts on Vector? > > P.S. The functionality in this proposal can be tested/tried out at > https://pecl.php.net/teds (under the class name > \Teds\Vector instead of \Vector). > (That is a PECL I created earlier this year for future versions of iterable proposals, common > data structures such as Vector/Deque, and less commonly used data structures that may be of use in > future work on implementing other data structures) > > Thanks, > Tyson > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: https://www.php.net/unsub.php > -- Pierre @pierrejoye | http://www.libgd.org