----- Original Message -----
From: "Man-wai Chang" <toylet.toylet@xxxxxxxxx>
To: <php-general@xxxxxxxxxxxxx>
Sent: Wednesday, April 25, 2007 3:23 PM
Subject: ${}
where can I find the documentation about this "symbol"?
It is one of those almost hidden treasures that is documented, a little bit
here and there, but it doesn't have a page on its own.
It is used to dissambiguate complex variables, specially when embedded
within double-quoted strings, so the interpreter knows how far does the
variable name and its parts go and when the rest of the string goes. For
example, if withing a double-quoted or heredoc string, the variable name is
immediately followed by a text or number without any spaces in between, the
interpreted can't know whether those characters are part of the variable
name or not. Also, when you want to refer to an array element or an object
property, the resulting expression might get somewhat more complicated and
there might be ambiguities as to how far does the variable goes and where
the rest of the string goes.
It might also be used to generate variable names on the fly, ${'variable' .
$i} will produce the contents of $variable0 for $i = 0.
I think it was also used to refer to individual characters within a string
as if it was a character array, but that is deprecated in favour of square
brackets.
Satyam
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