Today I learned PHP filters. I really enjoy the PHP language while I am learning it.

    TIL (thanks to sneakyimp) that you can do...

    16:16 $ /usr/bin/php -a
Interactive shell

php > $😊 = 'happy';
php > echo $😊;
happy
php >

    you can define emoji classes and namespaces, too:

    class 😊 {
  public static function ☚ī¸(){
    echo "🎭\n";
  }
}
😊::☚ī¸();
    6 days later
    4 days later

    Today I learned how to turn my old laptop into a server at home

    sneakyimp Running it on windows machine

    Today I learned to set up virtual machines and pint to different projects

        3 months later

        Okay, so array_map(null, $array1, $array2, $array, ...) can be used to zip several arrays together. array_map(null, [1,2,3], [4,5,6]) == [[1,4], [2,5], [3,6]]. And then you've got the destructuring operator "..." and now you can have a general array-transpose operation:

        $array = [[1,2,3], [4,5,6], [7,8,9]];
array_map(null, ...$array) == [[1,4,7], [2,5,8], [3,6,9]];

        Which is all well, and good. But TIL:

        array_map(null, ...[[a,b,c], [d,e,f], [g,h,i], [j,k,l]]) == [[a,d,g,j], [b,e,h,k], [c,f,i,l]]
array_map(null, ...[[a,b,c], [d,e,f], [g,h,i]]) == [[a,d,g], [b,e,h], [c,f,i]]
array_map(null, ...[[a,b,c], [d,e,f]]) == [[a,d], [b,e], [c,f]]
array_map(null, ...[[a,b,c]]) == [a, b, c]

        4 arrays of 3 elements each becomes 3 arrays of 4 elements each
        3 arrays of 3 elements each becomes 3 arrays of 3 elements each
        2 arrays of 3 elements each becomes 3 arrays of 2 elements each
        1 array  of 3 elements each becomes 1 array  of 3 elements each
        One of these things is not like the others. And apparently it's not a bug. array_map(null, ...[[a,b,c]]) is equivalent to array_map(null, [a,b,c]) as it should be, but it was decided that the latter should be a no-op and just return its second argument unchanged.

        Weedpacket

        if(!is_array($new_array[0])) {
    $new_array = [$new_array];
}

        🙃

        (It's been years since I touched array_map() -- thankfully? -- and have never run into that syntax, and kind of hope I never have a reason to use it. 😉 )

          Weedpacket You don't like functional programming?

          Not a question of like/dislike, but more that I've not pursued it, other than reading/viewing a few high-level discussions at mainly theoretical levels -- no practical experience (intentionally) implementing it.

            NogDog Ah; your mention of "hope" made me think you had something against it.

            For fun and the record, here's the method where I hit the snag, with the workaround included, just to give an idea of what things would start to look like without the array_map.

            public function ConjunctionVisit(Conjunction $expr)
{
	// Look for substitutions to Conjunction-bound variables. If this happens (it shouldn't, but at present
	// there's nothing to stop it), we first replace the Conjunction's colliding bound variables with
	// newly-minted ones, then update its expression to use the newly-minted variables in place of
	// the existing ones. Then we can apply the substitutions we were actually passed.
	$new_substitutions = [];
	foreach($this->substitutions as [$var,])
	{
		if(in_array($var, $expr->variables, true))
		{
			$new_substitutions[] = [$var, LVariable()];
		}
	}
	if(empty($new_substitutions))
	{
		// No substitutions of bound variables. Business as usual, then.
		$expression = $expr->expression->accept($this);
		return ($expression === $expr->expression) ? $expr : Conjunction($expression, $expr->variables);
	}

// If the number of new substitutions is 1 then array_map(null, ...) breaks down
// (this is known but undocumented behaviour: array_map(null, array) is a no-op)
if(count($new_substitutions) == 1)
{
	$existing_variables = [$new_substitutions[0][0]];
	$new_variables = [$new_substitutions[0][1]];
}
else
{
	[$existing_variables, $new_variables] = array_map(null, ...$new_substitutions);
}
$new_variables = array_map(function($var)use($existing_variables, $new_variables)
{
	$i = array_search($var, $existing_variables, true);
	return ($i !== false) ? $new_variables[$i] : $var;
}, $expr->variables);
return Conjunction($expr->expression->accept(Substituting(...$new_substitutions, ...$this->substitutions)), $new_variables);
}

              Weedpacket your mention of "hope" made me think you had something against it

              Nah, more that I had recollections of trying to use array_map() for something way back when and finding it less than easy to comprehend at the time, and that this twist on it looked like it might cause a similar mind-ache. 🙂 (Hopefully I'm a bit better programmer now and maybe it would come more easily, but the situation has not arisen since then where I ended up on the manual page for array_map().)

                  3 months later

                  TIL: you can flip an image horizontally just via CSS:

                  <img src='/smurf.gif' height="150px" style="transform: scaleX(-1);">

                  PS: Yes, I'm using a "Smurf" image for an internal tool on a project which ended up with the acronym "SMRF". 🙂

                  18 days later

                  NogDog You could substitute an image of Papa Smurf over the Christmas season.

                      12 days later

                      TIL: looks like strtotime() ignores fractional seconds when converting an ISO 8601 timestamp:

                      $ php -r 'var_dump(strtotime("2021-09-21T22:19:51.689+00:00"));'
int(1632262791)
$ php -r 'var_dump(strtotime("2021-09-21 15:19:52"));'
int(1632262792)

                        Also learned that floor(), ceil(), and round() return floats for some reason:

                        $ php -r 'var_dump(ceil("1.1"));'
float(2)
$ php -r 'var_dump(floor("1.1"));'
float(1)
$ php -r 'var_dump(round("1.1"));'
float(1)