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To: Mike Schinkel <mike@newclarity.net>, PHP internals
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Thread-Topic: [PHP-DEV] Initializing constants once, with code?
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Date: Sat, 25 Jan 2020 03:37:22 +0000
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Subject: Re: [PHP-DEV] Initializing constants once, with code?
From: tysonandre775@hotmail.com (tyson andre)

I've also put together a *different* proof of concept adding support for na=
med calls of global functions=0A=
(and only that, no other new allowed types of expressions) from within the =
expressions of constants.=0A=
(i.e. global constants, class constants, and parameter defaults).=0A=
=0A=
I was considering putting together an RFC to allow function calls=0A=
once I'm finished implementing that,=0A=
and if no major unfixable issues are identified.=0A=
=0A=
https://github.com/TysonAndre/php-src/pull/12 allows expressions such as:=
=0A=
=0A=
   <?php class X { const MESSAGE =3D sprintf('hello, %s', 'world'); }=0A=
=0A=
This uses php's default behavior for evaluating constants,=0A=
which is delayed until the first use for class constants/param defaults,=0A=
and at the time of declaration for global constants.=0A=
=0A=
This POC will throw if the constant would be invalid (same checks as define=
()) (e.g. reject cycles, references, or objects),=0A=
and will also throw an Error if a function call tries to load the constant =
currently being defined.=