Bug #79044 [Com]: Curly Braces Throw T_LNUMBER Error

Edit report at https://bugs.php.net/bug.php?id=79044&edit=1 ID: 79044 Comment by: thebluewalrus at gmail dot com Reported by: thebluewalrus at gmail dot com Summary: Curly Braces Throw T_LNUMBER Error Status: Not a bug Type: Bug Package: *General Issues Operating System: Mac OSX 10.12.4 PHP Version: 7.4.1 Block user comment: N Private report: N New Comment: So the 'complex syntax' is not as advanced as the regular variable processor but the behavior of the 'complex syntax' will not be corrected because that is how it has been for ages? It would seem to me that \{\$[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*\} would be better than \{\$[^}]+?\} which is what I presume the regular variable processor uses. If it's not a variable it shouldn't process it. I can't see how this would break past functionality, Previously the complex failed in instance where it shouldn't have. Previous Comments: ------------------------------------------------------------------------ [2019-12-30 00:04:54] bugreports at gmail dot com > Unless, of course, you have a compelling reason why > PHP should suddenly break functionality that has > been allowed since basically forever? well, nobody right in his mind would write "$1test" instead "\$1test" and call that simply *udenfeined* hehavior given that yiu are supposed to escape $ within double quotes and undefined behavior by it's definition can change at whatever point in time ------------------------------------------------------------------------ [2019-12-29 23:42:48] requinix@php.net > irrelevant By all means, please invent a time machine and go back a couple decades to tell the people developing PHP that they should have done this differently. That way people in the other timeline won't have to deal with such utterly ridiculous behavior. I know that for me, personally, if I were to fork PHP, prohibiting writing "$1" is at the top of my list of things to change. Meanwhile for those of us in this timeline, that's how it is. Unless, of course, you have a compelling reason why PHP should suddenly break functionality that has been allowed since basically forever? If you actually do despite my sarcasm, go ahead and start working on an RFC for it. I'm sure everyone will love it. ------------------------------------------------------------------------ [2019-12-29 23:10:49] bugreports at gmail dot com irrelevant, the second one should throw the same error than the first and that can even throw at compile time php > echo $1test; Parse error: syntax error, unexpected '1' (T_LNUMBER), expecting variable (T_VARIABLE) or '{' or '$' in php shell code on line 1 php > echo "$1test"; $1test ------------------------------------------------------------------------ [2019-12-29 22:44:18] requinix@php.net Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://www.php.net/manual/ and the instructions on how to report a bug at http://bugs.php.net/how-to-report.php https://www.php.net/manual/en/language.types.string.php#language.types.string.parsing When PHP reads the simple syntax it sees the '$' and takes > as many tokens as possible to form a valid variable name No tokens means no variable and PHP ignores it. Complex syntax works differently as it > allows for the use of complex expressions With complex syntax PHP sees '{$' and everything up to the closing '}' is used. In other words, PHP looks for a valid expression - the kind you use in your regular code, but with the obvious limitation that it has to start with a dollar sign. "$1" is not a valid expression, and PHP raises the same syntax error that it would as if you wrote that outside of a string. ------------------------------------------------------------------------ [2019-12-29 21:21:15] thebluewalrus at gmail dot com Yes, I agree I would expect '"$1"' and '"{$1}"' to behave the same but they don't. I think one or the other is functioning incorrectly. Simplifying the "correct" example it still executes: preg_replace('/(a)/', "$1", 'a'); ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=79044 -- Edit this bug report at https://bugs.php.net/bug.php?id=79044&edit=1