Re: Re: optimilize web page loading

At 10:59 AM -0400 3/28/08, Robert Cummings wrote:

Nope, when processing a single quoted string there should be 4 available parse branches:

    EOF
    '    (end of string)
    \
        EOF
        \
        '
        anything else
    anything else

Whereas with a double quoted string you have something along the lines of:

    EOF
    "    (end of string)
    $    (begin variable)
    {    (possible begin interpolation)
        $    (begin interpolation)
    \
        EOF
        \
        '
        "
        t
        n
        r
        x
        v
        f
        <digit>
        anything else
    anything else

So presuming no variable is embeded and assuming no escaped characters... double quotes still need to check for the beginning of variable interpolation which has 2 different start possibilities. With respect to creating the byte code single quotes have 4 branches, double quotes have 6 branches in the simplest of cases with no escape and no interpolation. So one would expect compile time for double quotes to be approximately 33% slower than for single quotes. Once compiled though, the point is moot especially since most sites use a bytecode cache like eAccelerator or APC. Even without a cache htough, the time difference is teeeeeeeency, and this is just for informational purposes :) There are usually bigger eggs to fry when optimizing. One last thing though... even if this were escaped and even if there were fifty variables embedded, a good bytecode optimizer (not quite the same as a bytecode cacher) would optimize the bytecode for caching so that the string is broken up according to what needs to be interpolated and what does not.

As always, thanks for your most excellent explanation. I figured that something along those lines was happening. I didn't consider the escape concerns. Cheers, tedd -- ------- http://sperling.com http://ancientstones.com http://earthstones.com