Description:
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First, switch/case compares values using *loose* equality (==) which causes issues with null, 0, "" etc. and requires ugly hacks, for instance: https://github.com/doctrine/orm/commit/a9bca86d4d06557b8159b82b2de0b6f678c9dffd

I almost always want *strict* equality (===).

Idea of syntax (related to the second idea below):

    switch ( EXPR ) using strict_equality { CASES }

(note: that syntax is open to debate, but in any case I would *not* want a declare()).


Second (but far less important), sometimes I would like to use a switch/case with a custom comparison (instead of equality).

Idea of syntax (related to the first idea above):

    switch ( EXPR ) using ( BINARY_PREDICATE ) { CASES }

Examples:

    switch (getSomeString()) using ('str_starts_with') {
        case 'foo_':
        case 'bar_':
            /* starts with "foo_" or "bar_" */
            break;
        case 'qux_2_':
            /* starts with "qux_2_" */
            // no break
        case 'qux_':
            /* starts with "qux_" */
            break;
        default:
            /* doesn't start with any of the above */
    }

    switch (getSomeString()) using (fn($value, $case) => (bool) preg_match($case, $value)) {
        case '/^(0|-?[1-9]\d*)$/D':
            /* ... */
            break;
        case '/^[[:xdigit:]]{2}$/D':
            /* ... */
            break;
        // ...
    }

    switch (getSomeInt()) using (fn($value, $case) => $value >= $case) {
        case 50:
            /* >= 50 (i.e. in range(50, \PHP_INT_MAX)) */
            break;
        case 10:
            /* in range(10, 49) */
            break;
        case 0:
            /* in range(0, 9) */
            break;
        default:
            /* < 0 (i.e. in range(\PHP_INT_MIN, -1)) */
    }

And as a bonus, it would be even nicer if it could handle specifying built-in comparison operators directly like e.g. "using (>=)" (or maybe "using >="), in which case maybe "using strict_equality" wouldn't be needed.

But again, let's not let extra wishes hinder the most wanted: strict switch.


Thoughts?