Sophie: php-manual-en-4.3.0-2mdk noarch

php-manual-en-4.3.0-2mdk.noarch.rpm

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>Expression types</H1
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>&#13;   PHP/FI 2.0 used the left side of expressions to determine what type
   the result should be.  PHP 3.0 takes both sides into account when
   determining result types, and this may cause 2.0 scripts to behave
   unexpectedly in 3.0.
  </P
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>&#13;   Consider this example:
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>$a[0]=5;
$a[1]=7;

$key = key($a);
while ("" != $key) {
    echo "$keyn";
    next($a);
}</PRE
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>

   In PHP/FI 2.0, this would display both of $a's indices.  In PHP
   3.0, it wouldn't display anything.  The reason is that in PHP 2.0,
   because the left argument's type was string, a string comparison
   was made, and indeed <TT
CLASS="literal"
>""</TT
> does not equal
   <TT
CLASS="literal"
>"0"</TT
>, and the loop went through.  In PHP 3.0,
   when a string is compared with an integer, an integer comparison is
   made (the string is converted to an integer).  This results in
   comparing <TT
CLASS="literal"
>atoi("")</TT
> which is
   <TT
CLASS="literal"
>0</TT
>, and <TT
CLASS="literal"
>variablelist</TT
> which is
   also <TT
CLASS="literal"
>0</TT
>, and since <TT
CLASS="literal"
>0==0</TT
>, the
   loop doesn't go through even once.
  </P
><P
>&#13;   The fix for this is simple.  Replace the while statement with:
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