rfc:dynamic_class_constant_fetch

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rfc:dynamic_class_constant_fetch [2022/11/04 14:11] – created ilutovrfc:dynamic_class_constant_fetch [2023/02/02 17:17] (current) – Move to implemented ilutov
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   * Date: 2022-11-04   * Date: 2022-11-04
   * Author: Ilija Tovilo, tovilo.ilija@gmail.com   * Author: Ilija Tovilo, tovilo.ilija@gmail.com
-  * Status: Draft+  * Status: Implemented
   * Target Version: PHP 8.3   * Target Version: PHP 8.3
   * Implementation: https://github.com/php/php-src/pull/9793   * Implementation: https://github.com/php/php-src/pull/9793
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   - Methods <php>$foo->{$bar}()</php>   - Methods <php>$foo->{$bar}()</php>
   - Static methods <php>Foo::{$bar}()</php>   - Static methods <php>Foo::{$bar}()</php>
 +  - Classes for static properties <php>$foo::$bar</php>
   - Classes for static methods <php>$foo::bar()</php>   - Classes for static methods <php>$foo::bar()</php>
  
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 ==== {} expression type ==== ==== {} expression type ====
  
-The result of the expression in the braces <php>{}</php> must be of type <php>string</php>. If it is not, an +The result of the expression in the braces <php>{}</php> must be of type <php>string</php>. If it is not, a 
-<php>Error</php> is thrown.+<php>TypeError</php> is thrown.
  
 <code php> <code php>
 echo Foo::{[]}; echo Foo::{[]};
-// Error: Illegal offset type+// TypeError: Cannot use value of type array as class constant name
 </code> </code>
  
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 // Can't be demonstrated because there is no __getStatic // Can't be demonstrated because there is no __getStatic
-// Foo::${test('foo')}::${test('bar')};+Foo::${test('foo')}::${test('bar')};
 // foo // foo
 // Static property foo // Static property foo
 // bar // bar
 // Static property bar // Static property bar
-</php>+</code>
  
-Property and array accesses evaluate all expressions in the chain before performing any of the actual operations. For +Property and array accesses evaluate all expressions in the chain before performing any of the actual operations. The reason for this is rather [[https://www.npopov.com/2017/04/14/PHP-7-Virtual-machine.html#writes-and-memory-safety|technical]]. Basically, no userland code must run between property or array accesses to avoid reallocation and thus potentially invalidating pointers. This problem does not apply to class constants. Thus, the simpler and more intuitive in-order approach is chosen. Evaluation order for class constants is also unlikely to matter since chaining them is of dubious usefulness.
-constants, order is less relevant because it's very rare for them to be chained. Thus, the simpler approach is chosen, +
-which is evaluating them in order.+
  
 <code php> <code php>
-// Foo::{test('foo')}::{test('bar')};+Foo::{test('foo')}::{test('bar')};
 // foo // foo
 // Class constant foo // Class constant foo
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 ===== Vote ===== ===== Vote =====
  
-Voting starts ??? and ends ???. +Voting starts 2022-12-22 and ends 2023-01-05. 
  
 As this is a language change, a 2/3 majority is required. As this is a language change, a 2/3 majority is required.
rfc/dynamic_class_constant_fetch.1667571070.txt.gz · Last modified: 2022/11/04 14:11 by ilutov

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