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Cannot pass null argument when using type hinting
...
PHP 7.1 or newer (released 2nd December 2016)
You can explicitly declare a variable to be null with this syntax
function foo(?Type $t) {
}
this will result in
$this->foo(new Type()); // ok
$this->foo(null); // ok
$...
Difference between “!==” and “==!” [closed]
Yesterday I stumbled over this when I modified PHP code written by someone else. I was baffled that a simple comparison ( if ($var ==! " ") ) didn't work as expected. After some testing I realized that whoever wrote that code used ==! instead of !== as comparison operator. I've never seen ==! ...
Returning first x items from array
... 6);
array_splice($input, 5); // $input is now array(1, 2, 3, 4, 5)
From PHP manual:
array array_splice ( array &$input , int $offset [, int $length = 0 [, mixed $replacement]])
If length is omitted, removes everything from offset to the end of the array. If length is specified and is posit...
Change R default library path using .libPaths in Rprofile.site fails to work
...tudio
In your case it appears that RStudio is not respecting the Rprofile.site settings or perhaps is overriding them by reading an .Rprofile setting from one of the RStudio defaults. It should also be mentioned that the result from this operation also appends the contents of calls to .Library and ...
JOIN queries vs multiple queries
...specific case. It depends on a lot of things. Jeff Atwood (founder of this site) actually wrote about this. For the most part, though, if you have the right indexes and you properly do your JOINs it is usually going to be faster to do 1 trip than several.
...
Ways to circumvent the same-origin policy
...n receiveMessage(event)
{
// do something with event.data;
}
The off-site iframe must also send events properly via postMessage:
<script>window.parent.postMessage('foo','*')</script>
Any window may access this method on any other window, at any time, regardless of the location o...
Show a PDF files in users browser via PHP/Perl
...
<?php header('Content-type: application/pdf'); header('Content-Disposition: inline; filename="the.pdf"'); readfile('/dir/to/the.pdf'); ?>
– dimassony
Jan 13 '11 at 13:10
...
How can I develop for iPhone using a Windows development machine?
... hackintosh info gets outdated pretty easily, it is better to follow the sites that are dedicated to the subject (like osxlatitude for dell models)
– prusswan
Oct 2 '14 at 7:26
...
Sending a JSON to server and retrieving a JSON in return, without JQuery
... }
};
xhr.send();
Handling data in JSON format on the server-side using PHP
<?php
// Handling data in JSON format on the server-side using PHP
//
header("Content-Type: application/json");
// build a PHP variable from JSON sent using POST method
$v = json_decode(stripslashes(file_get_contents(...
MySQL, Check if a column exists in a table with SQL
...his works well for me.
SHOW COLUMNS FROM `table` LIKE 'fieldname';
With PHP it would be something like...
$result = mysql_query("SHOW COLUMNS FROM `table` LIKE 'fieldname'");
$exists = (mysql_num_rows($result))?TRUE:FALSE;
...