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<HTML
><HEAD
><TITLE
>What References Are Not</TITLE
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>What References Are Not</A
></H1
><P
> As said above, references aren't pointers. That means, the
following construct won't do what you expect:
<DIV
CLASS="informalexample"
><A
NAME="AEN3933"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
> function foo (&$var) {
$var =& $GLOBALS["baz"];
}
foo($bar);
</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
</P
><P
> What will happen that <TT
CLASS="varname"
>$var</TT
> in foo will be bound
with <TT
CLASS="varname"
>$bar</TT
> in caller, but then it will be
re-bound with <TT
CLASS="varname"
>$GLOBALS["baz"]</TT
>. There's no way
to bind <TT
CLASS="varname"
>$bar</TT
> in the caller to something else
using reference mechanism, since <TT
CLASS="varname"
>$bar</TT
> is not
available in the function foo (it is represented by
<TT
CLASS="varname"
>$var</TT
>, but <TT
CLASS="varname"
>$var</TT
> has only
variable contents and not name-to-value binding in the calling
symbol table).
</P
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