rfc:normalize-array-auto-increment-on-copy-on-write

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rfc:normalize-array-auto-increment-on-copy-on-write [2019/06/19 22:56] – wesnetmorfc:normalize-array-auto-increment-on-copy-on-write [2019/06/28 21:07] – wesnetmo
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-====== PHP RFC: Normalize array's "auto-increment" value on copy on write ======+====== PHP RFC: Normalize arrays' "auto-increment" value on copy on write ======
  
   * Version: 0.1   * Version: 0.1
   * Date: 2019-06-19   * Date: 2019-06-19
   * Author: Wes (@WesNetmo)   * Author: Wes (@WesNetmo)
-  * Status: Under Discussion+  * Status: Voting
   * First Published at: http://wiki.php.net/rfc/normalize-array-auto-increment-on-copy-on-write   * First Published at: http://wiki.php.net/rfc/normalize-array-auto-increment-on-copy-on-write
  
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 </PHP> </PHP>
  
-This is currently not guaranteed, and due to PHP ''array''s' nature, it is not possible to +This is currently not guaranteed, and because of ''array''s' all-doing nature, it is not 
-always enforce this property -- but it should be, at least in some dangerous cases.+possible to always enforce this property -- but it should be in some dangerous cases, 
 +namely when functions from (potential) different authors are interacting. 
 + 
 +-----
  
 When an ''array'' is assigned to a new reference, and it is copied, before a modification, When an ''array'' is assigned to a new reference, and it is copied, before a modification,
 due to the copy-on-write behavior, it will result in an ''array'' that is identical in any due to the copy-on-write behavior, it will result in an ''array'' that is identical in any
-way to the original one; in fact, the copy also covers the "auto-increment" value:+way to the original one, inclusive of its "auto-increment" value:
  
 <PHP> <PHP>
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 </PHP> </PHP>
  
-This behavior happens, unfortunately, also between different scopes. Our functions can + 
-receive "broken" ''array''-lists from third-parties that only appear to be well-indexed, +This happens also between different function scopes. Our functions can receive "broken" 
-but that in reality are not, because they were misused during their lifetime (for example, +''array''-lists from third-parties that only appear to be well-indexed, but that in 
-it was used ''unset()'' on them, instead of ''array_pop()'').+reality are not, because they were misused during their lifetime (classic example, it was 
 +used ''unset($array[$lastIndex])'' on them, instead of ''array_pop($array)'').
  
 As result of that, despite "copy on write", the value-type semantics, and even a different As result of that, despite "copy on write", the value-type semantics, and even a different
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 be considered a bug-fix, rather than a behavior change; it offers protection against be considered a bug-fix, rather than a behavior change; it offers protection against
 ''array''-lists that were misused with ''unset()'' instead of ''array_pop/_splice/_shift'' ''array''-lists that were misused with ''unset()'' instead of ''array_pop/_splice/_shift''
-and thus will only affect code that should already be improved. Furthermore, the +and thus will only affect code that is already a candidate for improvements. Furthermore, 
-"auto-increment" value is copied inconsistently already, when the ''array'' is empty:+the "auto-increment" value is copied inconsistently, when the ''array'' is empty:
  
 <PHP> <PHP>
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 // $b is [0 => 2], rather than [2 => 2] // $b is [0 => 2], rather than [2 => 2]
 </PHP> </PHP>
 +
 +The proposed change would make the behavior consistent and safer.
  
 ===== Proposed PHP Version(s) ===== ===== Proposed PHP Version(s) =====
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 Vote will require 2/3 majority Vote will require 2/3 majority
  
 +<doodle title="Normalize the auto-increment value on array copy?" auth="wesnetmo" voteType="single" closed="false">
 +   * Yes
 +   * No
 +</doodle>
 +
 +===== References  =====
 +
 +  * [[https://externals.io/message/105992|Pre-vote discussion on externals.io]]
rfc/normalize-array-auto-increment-on-copy-on-write.txt · Last modified: 2019/06/28 21:13 by wesnetmo

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