Re: [Discussion] Why can't I do "{$a::class}"?

Hi Peter On Sun, May 19, 2024 at 10:30 AM Peter Stalman <sarkedev@gmail.com> wrote: > > echo " {A::$static_property} \n"; // doesn't work (unless $static_property is a > variable) > echo " {$a::$static_property} \n"; // works > > echo " {A::static_method()} \n"; // doesn't work (just text) > echo " {$a::static_method()} \n"; // works > > echo " {A::constant} \n"; // doesn't work > echo " {$a::constant} \n"; // doesn't work either, but why? It would be straightforward to allow all expressions that start with a $ in string interpolation, as I've noticed a couple of years ago [1]. This restriction seems rather arbitrary. I think I held off proposing this because I was planning on proposing a more complete form of string interpolation [2]. However, the backwards-compatible syntax was largely disliked, so I withdrew the RFC. I wasn't particularly fond of introducing more forms of strings (e.g. $"", f"", etc.) to avoid the BC break, because there are already plentiful: * '' * "" * `` (yes, these allow interpolation) * <<<HD ... HD * <<<'HD' ... HD Adding at least the two expected ones ($"" and $<<<HD ... HD) would bump that up to 7 forms. There were also suggestions to extend strings in a more generic way, akin to JavaScripts template strings [3], but I didn't have any use for this myself. Ilija [1] https://github.com/php/php-src/compare/master...iluuu1994:php-src:lift-variable-restriction-for-brace-dollar-string-interpolation [2] https://wiki.php.net/rfc/arbitrary_string_interpolation [3] https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals