Re: Power function as operator

Hi, On Sat, Nov 23, 2013 at 1:14 AM, Leigh <leight@gmail.com> wrote: > Definitely something that is missing and would be a welcome addition. > > Where have you placed it in terms of operator precedence? > It was equal to the shift operators and left associative, which was most definitely wrong ;-) I've now changed the operator precedence to one higher than ~ (bitwise not) and right associative. So: -3 ** 2 == -9 ~3 ** 2 == -10, 2 ** 3 ** 2 == 512 I should probably add this in a test case as well =D > On 22 November 2013 16:58, Tjerk Meesters <tjerk.meesters@gmail.com> > wrote: > > Hi, > > > > To challenge myself I had tasked myself to introduce a new operator and > > opcode to the language; now that I'm done with it, I wanted to measure > the > > response on the list to actually get it merged before writing an RFC. > > > > My work can be found here: > > https://github.com/datibbaw/php-src/compare/pow-operator > > > > It introduces the pow() function as an operator ** (double asterisk), as > > can be found in languages such as Python (with perhaps the notable > > difference that it's right associative there). > > > > The logic gets exposed via the ZEND_POW opcode and all the logic that > went > > into pow() itself is copied into it. The exceptions are that an > expression > > such as [] ** 2 (squared empty array) will cause a fatal error because > the > > operands are incompatible, whereas pow([], 2) would give 0. > > > > Why this operator? Basically because: > > 1) it's shorter (the keyboard rejoices). > > 2) it's faster (no ZEND_CALL). > > 3) it's found in other languages too. > > > > I've only implemented one of the test suites; there are quite a few for > > just one function, but when needed I can add those others as well. > > > > Btw, changes to vld aren't pushed yet. > > > > Let me know! > > > > -- > > -- > > Tjerk > -- -- Tjerk