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To: Christian Schneider <cschneid@cschneid.com>
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Thread-Topic: [PHP-DEV] RFC idea: Block scoped variables with "let $x = expr"
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Date: Sun, 15 Mar 2020 17:42:40 +0000
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Subject: Re: [PHP-DEV] RFC idea: Block scoped variables with "let $x = expr"
From: tysonandre775@hotmail.com (tyson andre)

>=A0What you are suggesting is that a let statement would switch PHP to an =
altogether different mode where function-scoped and explicit global variabl=
es were suddenly disallowed and an error within that function (or only afte=
r the let?).=A0=0A=
=0A=
No, the variables with the *same name* as the variables in any "let" in tha=
t function body would be disallowed. In this proposal, variables, parameter=
s, and closure uses with different names can be declared and used normally.=
=0A=
=0A=
I mentioned $GLOBALS as one of the ways in which this proposal is a best-ef=
fort. However, I'm not proposing to ban $GLOBALS (but to ban $$var).=0A=
=0A=
- The top-level statements of the file can either be the global variables o=
r the variables in the function which required the file. It's not known whi=
ch at compile time, so I don't plan to ban $GLOBALS.=0A=
=0A=
> That sounds like a bad idea to me as I'd have to look at the whole functi=
on to see if there is a let somewhere to determine the function's/variable'=
s mode.=0A=
=0A=
A developer would run `php --syntax-check` to know if the variable is being=
 accessed incorrectly in a file.=0A=
Various tools or scripts exist to do that, in Continuous Integration or in =
editors/IDEs.=0A=
=0A=
If you meant something else, could you give a code example?=0A=
=0A=
- Tyson=