rfc:variadic_empty
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rfc:variadic_empty [2015/02/21 03:11] tpunt |
rfc:variadic_empty [2017/09/22 13:28] |
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| - | ====== PHP RFC: Make empty() a Variadic ====== | ||
| - | * Version: 0.1 | ||
| - | * Date: 2015-02-20 | ||
| - | * Author: Thomas Punt, tpunt@hotmail.co.uk | ||
| - | * Status: Draft | ||
| - | * First Published at: http://wiki.php.net/rfc/variadic_empty | ||
| - | ===== Introduction ===== | ||
| - | This RFC aims to make the ''empty'' language construct accept any number of arguments. | ||
| - | |||
| - | <code php> | ||
| - | // example current usage #1: | ||
| - | if (empty($a) || empty($b) || empty($c)) {} | ||
| - | |||
| - | // example current usage #2: | ||
| - | if (!empty($a) && !empty($b) && !empty($c)) {} | ||
| - | |||
| - | // new example usage #1: | ||
| - | if (empty($a, $b, $c)) {} | ||
| - | |||
| - | // new example usage #2: | ||
| - | if (!empty($a, $b, $c)) {} | ||
| - | </code> | ||
| - | |||
| - | ===== Proposal ===== | ||
| - | This RFC proposes to change ''empty()'' to have a variable arity, which will enable developers to write more compact code when checking for the emptiness of multiple expressions. | ||
| - | |||
| - | As the above snippet demonstrates, the semantics of a variadic ''empty()'' should be the equivalent to logically OR'ing multiple ''empty()'' invocations together. This behaviour seems to be the most useful, and given that ''empty()'' performs a reverse check to ''isset()'', it should have reversed semantics in order to make it inline. ... | ||
| - | |||
| - | ===== Justification ===== | ||
| - | |||
| - | ==== Common ==== | ||
| - | In PHP, it is not uncommon to see conditionals consisting of multiple ''empty()'' invocations. This is evident by simply browsing through some popular open source projects: | ||
| - | |||
| - | * WordPress (( https://github.com/WordPress/WordPress/blob/master/wp-admin/includes/template.php#L1963 )) | ||
| - | <code php> | ||
| - | if ( empty( $pointer_id ) || empty( $selector ) || empty( $args ) || empty( $args['content'] ) ) | ||
| - | </code> | ||
| - | * OpenCart (( https://github.com/opencart/opencart/blob/45fc863fa068d82b5280890e6466a198faa54bff/upload/admin/controller/openbay/ebay_profile.php#L128 )) | ||
| - | <code php> | ||
| - | if (empty($setting['dispatch_times']) || empty($setting['countries']) || empty($setting['returns'])){ | ||
| - | </code> | ||
| - | * phpBB (( https://github.com/phpbb/phpbb/blob/040d451dcca9ae54d8f4b7bdd2f231033765a8f2/phpBB/phpbb/notification/method/jabber.php#L48 )) | ||
| - | <code php> | ||
| - | return !( | ||
| - | empty($this->config['jab_enable']) || | ||
| - | empty($this->config['jab_host']) || | ||
| - | empty($this->config['jab_username']) || | ||
| - | empty($this->config['jab_password']) || | ||
| - | !@extension_loaded('xml') | ||
| - | ); | ||
| - | </code> | ||
| - | * And so on... | ||
| - | |||
| - | So this seems like quite a common need for users. | ||
| - | |||
| - | The second justification is that it will make ''empty()'' more inline with the ''isset()'', which is good for the principle of least surprise | ||
| - | |||
| - | ===== Backward Incompatible Changes ===== | ||
| - | No BC breakages. | ||
| - | |||
| - | ===== Proposed PHP Version(s) ===== | ||
| - | PHP 7.0 | ||
| - | |||
| - | ===== RFC Impact ===== | ||
| - | ==== To SAPIs ==== | ||
| - | None. | ||
| - | |||
| - | ==== To Existing Extensions ==== | ||
| - | None. | ||
| - | |||
| - | ==== To Opcache ==== | ||
| - | None. | ||
| - | |||
| - | ==== New Constants ==== | ||
| - | None. | ||
| - | |||
| - | ==== php.ini Defaults ==== | ||
| - | None. | ||
| - | |||
| - | ===== Open Issues ===== | ||
| - | None. | ||
| - | |||
| - | ===== Unaffected PHP Functionality ===== | ||
| - | The current functionality of ''empty()'' will be completely preserved. | ||
| - | |||
| - | ===== Future Scope ===== | ||
| - | None that I can think of. | ||
| - | |||
| - | ===== Proposed Voting Choices ===== | ||
| - | Include these so readers know where you are heading and can discuss the proposed voting options. | ||
| - | |||
| - | State whether this project requires a 2/3 or 50%+1 majority (see [[voting]]) | ||
| - | |||
| - | ===== Patches and Tests ===== | ||
| - | Links to any external patches and tests go here. | ||
| - | |||
| - | If there is no patch, make it clear who will create a patch, or whether a volunteer to help with implementation is needed. | ||
| - | |||
| - | Make it clear if the patch is intended to be the final patch, or is just a prototype. | ||
| - | |||
| - | ===== Implementation ===== | ||
| - | After the project is implemented, this section should contain | ||
| - | - the version(s) it was merged to | ||
| - | - a link to the git commit(s) | ||
| - | - a link to the PHP manual entry for the feature | ||
| - | |||
| - | ===== References ===== | ||
| - | Links to external references, discussions or RFCs | ||
| - | |||
| - | ===== Rejected Features ===== | ||
| - | Keep this updated with features that were discussed on the mail lists. | ||
rfc/variadic_empty.txt · Last modified: 2017/09/22 13:28 (external edit)