Re: Proposal: Arbitrary precision native scalar type

On Thu, Dec 7, 2023 at 11:27 PM Jordan LeDoux <jordan.ledoux@gmail.com> wrote: You are going to run into some very difficult corners on this one. For the > last... 8 years i guess? I have been working on an arbitrary precision > library for PHP in userland. It utilizes BCMath, ext-decimal, and GMP, > depending on what is installed and what kind of operation you are > performing. > > So, the functions that currently accept floats include functions such as > sin() or atan(). These > functions are not at all trivial to do to > arbitrary precision. In fact, the VAST majority of the work I have done on > my library has been to handle cases like "What do I do if the user wants > 2.921 ** 4.293810472934854?" or "How will I guarantee the precision that > the user requested for tan() in an efficient way?" > > Now, libmpdec is going to actually have implementations for most of this > stuff that you can call directly, but if the PHP function sin() > isn't > capable of *outputting* a decimal, then this isn't really > that much of an > improvement over the current situation. I mean, it's still something I > would support, but that's the area where some help from the engine goes a > VERY long way. > In my proposal, builtin functions are capable of returning decimals if they're fed with decimals. You're probably also going to need a way for a user to grab certain > constants to a given precision. I would think e and pi at the least. > > I have a lot of experience working on this problem space in PHP, and am > definitely willing to help. I looked into doing a libmpdec PHP integration > several years ago, but decided that voters were unlikely to give it a fair > shot, and so decided against it. If you're willing to try and roll the ball > up the hill though, I'll definitely help you. > Unfortunately, I'm not an expert in precise math. I definitely need help from experts like you. I appreciate your readiness. I understand that there are a lot of edge cases. I would propose to implement basics at first and then decide what to do with edge cases.