A few thoughts:
1. I agree with the sentiment that this syntactic sugar doesn't actually save any verbosity, so it's not really syntactic sugar at all. 2. There appears to now be another RFC by Pavel Patapau, specifically focused on a Guard statement as a new keyword (https://wiki.php.net/rfc/guard_statement), which now has its separate discussion. 3. As Thomas Lamy mentioned, I too would prefer a single keyword. Consider the following two examples: function foo($bar) { if ($bar === 1) return; if ($bar === 666) delete_everything(); } function foo($bar) { if ($bar === 1) return if ($bar === 666); delete_everything(); } Both would now be valid syntax, and IDEs would have a harder time warning about the misplaced semicolon in the second example. Wouldn't be very common, but still. 4. However, this RFC is interesting to me because there be a way to modify it to allow for less verbose refactoring, and kinda allowing returns to bubble up like exceptions do. I think it would only make sense if it's a "if not null then return" type of thing. Consider the following (a bit contrived, but I hope you get the point): function main_function() { $result = calculate($var); if ($result !== null) return $result; /* do other important stuff */ } function main_function() { ifnotnullreturn calculate($var); /* do other important stuff */ } Obviously not an ideal keyword, but this is the only thing I can think of where this type of syntactic sugar makes sense and decreases verbosity. Something similar can also be accomplished with exception though. 5. Finally, I think if we start putting several returns at the same indentation then the cognitive load increases because we can no longer tell if a return is actually a return at a glance. Thanks, Peter On Fri, May 15, 2020 at 11:58 AM Victor Bolshov <crocodil...@gmail.com> wrote: > > Hi internals, > > I think it's just as good to write: > if ($condition) return $retval; > Yes, there are subtle semantic differences the new syntax would emphasize, > but it doesn't feel like it justifies it. New syntax also means the need to > support it, for IDEs and other tools, static analysis tools, code-style tools > - and all that for a very tiny benefit, if any. > Cheers, > Victor > > Sent from Mailspring > (https://link.getmailspring.com/link/85c8412b-b04a-4853-8c4c-e270fcb35...@getmailspring.com/0?redirect=https%3A%2F%2Fgetmailspring.com%2F&recipient=aW50ZXJuYWxzQGxpc3RzLnBocC5uZXQ%3D), > the best free email app for work > On May 10 2020, at 5:49 pm, Ralph Schindler <ra...@ralphschindler.com> wrote: > > Hi! # Intro I am proposing what is a near completely syntactical addition > > (only change is to language.y) to the language. The best terminology for > > this syntax is are: `return if`, "return early", or "guard clauses". see: > > https://en.wikipedia.org/wiki/Guard_(computer_science) Over the past few > > years, I've seen a growing number of blog posts, conference talks, and even > > tooling (for example code complexity scoring), that suggest writing guard > > clauses is a good practice to utilize. I've also seen it more prevalent in > > code, and even attempts at achieving this with Exceptions (in an HTTP > > context) in a framework like Laravel. see abort_if/throw_if: > > https://laravel.com/docs/7.x/helpers#method-abort-if It is also worth > > mentioning that Ruby has similar features, and I believe they are heavily > > utilized: see: > > https://github.com/rubocop-hq/ruby-style-guide#no-nested-conditionals # > > Proposal In an effort to make it a first class feature of the language, and > > to make the control flow / guard clause > s more visible when scanning code, I am proposing this in the syntax of > adding `return if`. The chosen syntax is: return if ( if_expr ) [: > optional_return_expression] ; As a contrived example: function > divide($dividend, $divisor = null) { return if ($divisor === null || $divisor > === 0); return $dividend / $divisor; } There is already a little discussion > around the choice of order in the above statement, the main take-aways and > (my) perceived benefits are: - it keeps the intent nearest the left rail of > the code (in normal/common-ish coding standards) - it treats "return if" as a > meta-keyword; if must follow return for the statement to be a guard clause. > This also allows a person to more easily discern "returns" from "return ifs" > more easily since there is not an arbitrary amount of code between them (for > example if the return expression were after return but before if). - it has > the quality that optional parts are towards the end - is also has the quality > that the : return_expression; > is very symmetrical to the way we demarcate the return type in method > signatures "): return type {" for example. - has the quality of promoting > single-line conditional returns # Finally One might say this is unnecessary > syntactic sugar, which is definitely arguable. But we do have multiple ways > of achieving this. Of course all of these things should be discussed, I think > sub-votes (should this PR make it that far) could be considered. The PR is > located here: https://github.com/php/php-src/pull/5552 As mentioned, some > discussion is happening there as well. Thanks! Ralph Schindler PS: since > implementing the ::class feature 8 years ago, the addition of the AST > abstraction made this kind of syntactical change proof-of-concept so much > easier, bravo! -- PHP Internals - PHP Runtime Development Mailing List To > unsubscribe, visit: http://www.php.net/unsub.php > -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
