Re: [RFC] Binary String Comparison

On 19.08.2014 05:07, Tjerk Meesters wrote:

On Mon, Aug 18, 2014 at 11:30 PM, Johannes Schlüter <johannes@schlueters.de <mailto:johannes@schlueters.de>> wrote:

    On Mon, 2014-08-18 at 23:09 +0800, Tjerk Meesters wrote:

On 18 Aug, 2014, at 10:47 pm, Johannes Schlüter

    <johannes@schlueters.de <mailto:johannes@schlueters.de>> wrote:

On Mon, 2014-08-18 at 14:44 +0200, Marc Bennewitz wrote: The question isn't "What's wrong with ===, strcmp()?" but

    "What's wrong

with ==, <, >?". We have a standard way to compare two operands but currently

    we do some

magic things to solve something that don't need to be solved. Still it is a key property of the language which we can't

    simply change.

Also mind this: All input data are strings and some databases also return data as string. So code like if ($_GET['id'] > 0) or if ($db->fetchRow()[0] == 12) which is common will break. Those two cases will actually not be affected, it's strictly

    string<=>string comparisons that's being discussed here.

    Meaning that simple code you find everywhere, in every second tutorial

        foreach ($db->query("SELECT id, title FROM entries") as $row) {
            echo "<tr><td";
            if ($row[0] == $_GET['highlight_id']) {
                echo " background='#ff0000'";
            }
            echo ">".htmlentities($row[1])."</td></tr>";
        }

    will suddenly fail. How wonderful! (irony)

Not necessarily and certainly not by definition; reasons for failure are less obvious such as (but not limited to): "0" == "0.0" "11" == " 11" (but note that "11" == "11 " currently yields false) "0" == "" I'm not arguing for or against this behaviour change, but I found it necessary to clear up some apparent confusion as to what repercussions this proposal carries. Another approach of attempting to solve the common issue of comparing big numbers with '==' is to only enforce string-wise comparison if a number cast would cause precision loss. That's a good point, too

    johannes

    ps. yes, the example might be done nicer and better, it still represents
    a common pattern.

-- -- Tjerk