Differences

This shows you the differences between two versions of the page.

--- rfc:base_convert_improvements [2019/05/15 20:45] – Minor change for the second char exussum
+++ rfc:base_convert_improvements [2020/04/12 20:13] – Fix typo (effected should be affected) theodorejb
@@ Line 3: / Line 3: @@
   * Date: 2019-05-15
   * Author: Scott Dutton,php@exussum.co.uk
-  * Status: Draft
+  * Status: Accepted
   * First Published at: https://wiki.php.net/rfc/base_convert_improvements
@@ Line 9: / Line 9: @@
 ===== Introduction =====
-the base_convert family of functions(base_convert, bin2hex, hex2bin etc) are very accepting with their input arguments, you can pass any string to to them and they give a best effort of converting it.
+The base_convert family of functions(base_convert, binhex, hexbin etc) are very accepting with their input arguments, you can pass any string to to them and they give a best effort of converting it.
 For example base_convert("hello world", 16, 10); will return 237 with no warnings. What this does internally is base_convert("ed", 16, 10);
-Also negative numbers simply do not work, eg base_convert("-ff", 16, 10); will return 255.
+Also negative numbers simply do not work, eg base_convert("-ff", 16, 10); will return 255. (similar to above the "-" gets silently ignored).
+Experienced developers get caught out by this for example  https://gist.github.com/iansltx/4820b02ab276c3306314daaa41573445#file-getlines-php-L9
+In this case literal binary data was the input and the result was 0 (which is expected but not clear)
+Other functions affected by this are:
+  * decbin() - Decimal to binary
+  * bindec() - Binary to decimal
+  * decoct() - Decimal to octal
+  * octdec() - Octal to decimal
+  * dechex() - Decimal to hexadecimal
+  * hexdec() - Hexadecimal to decimal
+Other programming languages behave in a a similar way to this proposal
+ * Javascript - https://jsfiddle.net/c16b4usp/
+ * Python - https://repl.it/repls/OliveBlushingModem
+ * Go - https://play.golang.org/p/aLWg15c00Fy
+Javascript does work with larger numbers correctly, Python and Go work in a way which would be similar to PHP if this change was made.
 ===== Proposal =====
-II propose two changes to the base_convert family of functions.
+I propose two changes to the base_convert family of functions.
+=== Error on ignored characters ===
+When passed arguments that base_convert will ignore, also give a warning to the user informing them their input was incorrect.
+There is an exception in place for the second char, if base is 16 'x' is allowed eg "0xff", base 2 allows b and base 8 allows o. this fits in with common formats for these numbers
-=== Error on truncation ===
-When passed arguments that base_convert will ignore, also give a warning to the user.
-There is an exception in place for the second char, if base is 16 'x' is allowed eg "0xff", base 2 allows b and base 8 allows o.
 This can be raised to a full exception for a later PHP version (eg PHP 8)
@@ Line 28: / Line 54: @@
 ===== Backward Incompatible Changes =====
-=== Error on truncation ===
+=== Error on ignored characters ===
 No BC breaks for a warning, in the case of an exception there will be a BC break - Would suggest PHP 8 for this.
@@ Line 34: / Line 60: @@
 base_convert currently in the backend has a zend_ulong as its representation. We would need a zend_long. This will change the behavior of numbers in the range 9223372036854775807 - 18446744073709551615 but will allow negative numbers.
-This currently breaks a fair amount of unit tests that I will need to update if this change is accepted.  The unit tests are around extreme values
+This currently breaks a fair amount of unit tests that I will need to update if this change is accepted.  The unit tests are around extreme values.
+A secondary BC change would be people who have worked around this in userland code for example
+https://stackoverflow.com/a/7051224/1281385
+This change will break these work arounds
+Would suggest PHP8 for this change
@@ Line 64: / Line 98: @@
 ===== Future Scope =====
-N/A
+Allow base_convert to allow any length input and not be restricted to a 64 bit int type
 ===== Proposed Voting Choices =====
-Include these so readers know where you are heading and can discuss the proposed voting options.
+votes
+=== Error on ignored characters ===
+This vote will be to raise a E_DEPRECATED warning for PHP 7.4. Raising to be an InvalidArgumentException in PHP 8
+=== Allow negative arguments ===
+This vote will allow negative arguments in PHP 8
 ===== Patches and Tests =====
 https://github.com/php/php-src/pull/3911
-===== Implementation =====
-After the project is implemented, this section should contain
-  - the version(s) it was merged into
-  - a link to the git commit(s)
-  - a link to the PHP manual entry for the feature
-  - a link to the language specification section (if any)
+===== Vote =====
+Started 19th June 2019. Ends 3rd July 2019
+<doodle title="Raise deprecated error in 7.4 and raise to exception in PHP 8 for unknown characters" auth="exussum" voteType="single" closed="true">
+   * Yes
+   * No
+</doodle>
+<doodle title="Allow negative numbers to be converted in PHP 8" auth="exussum" voteType="single" closed="true">
+   * Yes
+   * No
+</doodle>
 ===== References =====
 https://bugs.php.net/bug.php?id=61740

Differences

Page Tools