Re: [RFC] Configurable callback to dump results of expressions in `php -a`

Hi internals, > I've created a new RFC > https://wiki.php.net/rfc/readline_interactive_shell_result_function > adding a way to configure a callback to be called to dump the value of single-expression > statements from php -a > (and an ini setting that can be disabled to prevent that callback from being called). > > Many REPLs (Read-Eval-Print Loops) for other programming languages that I'm familiar with > print a (possibly truncated) representation of the result of expressions, but PHP doesn't. > It would be useful to allow users to extend the functionality of the default interactive php > shell (php -a), > possibly with auto_prepend_file or through use of command wrappers/aliases, or after loading > the shell. > Prior to this RFC, there was no way to extend the interactive php shell in this way. > (I've seen https://github.com/bobthecow/psysh mentioned as > an alternative for php -a while investigating this, > but that's a shell written from scratch, and doesn't have some functionality from php > -a such as tolerance of fatal errors) > > Because PHP's interactive shell is written in C, adding new features or bug fixes is > inconvenient - it would require a lot > of time getting familiar with C programming, PHP's internals and memory management, > and with PHP's internal C ast representation. > It would be easier and more accessible to extend PHP's interactive shell through code > written in PHP rather than code written in C. > > This was among the proposed enhancements I brought up in > https://externals.io/message/111073 . > An earlier version of the implementation was also created months ago -  > https://github.com/php/php-src/pull/5962 Some of the feedback had mentioned that adding the ability to dump the results of expressions in the default shell only made sense if there was a default implementation included with this RFC. I plan to start a straw poll shortly, to measure interest with/without a proposed result expression dumper loaded by default. https://wiki.php.net/rfc/readline_interactive_shell_result_function_straw_poll Thanks, - Tyson