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Laravel Check If Related Model Exists
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In php 7.2+ you can't use count on the relation object, so there's no one-fits-all method for all relations. Use query method instead as @tremby provided below:
$model->relation()->exists()
generic solution working on...
Java: Detect duplicates in ArrayList?
... Would it be more efficient to tell the HashSet how much space to allocate: Set<T> set = new HashSet<T>(list.size());? Given a List parameter I think it is more efficient if it is common for the list to not contain duplicates.
– Paul Jackson
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Should I use a data.frame or a matrix?
...ter in the code of the function only new values were recorded into already allocated spaces, and there was no overhead of adding new rows to the DF. This makes the comparison even more fair, and it also made my job simpler as I did not need to rewrite anything further in the function. Just one line ...
mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to
...ion:
NOTE The mysql_ functions are deprecated and have been removed in php version 7.
Check $result before passing it to mysql_fetch_array. You'll find that it's false because the query failed. See the mysql_query documentation for possible return values and suggestions for how to deal with th...
Algorithm to randomly generate an aesthetically-pleasing color palette [closed]
...n in their web page.
http://tools.medialab.sciences-po.fr/iwanthue/index.php
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What is move semantics?
...start with a very simple string class which only holds a pointer to a heap-allocated block of memory:
#include <cstring>
#include <algorithm>
class string
{
char* data;
public:
string(const char* p)
{
size_t size = std::strlen(p) + 1;
data = new char[size]...
Run cron job only if it isn't already running
...'s just a shell script:
#!/bin/sh
if ps -ef | grep -v grep | grep doctype.php ; then
exit 0
else
/home/user/bin/doctype.php >> /home/user/bin/spooler.log &
#mailing program
/home/user/bin/simplemail.php "Print spooler was not running... Restarted."
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If my interface must return Task what is the best way to have a no-operation implementation?
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@Asad it reduces allocations (and with it GC time). Instead of allocation new memory and constructing a Task instance each time you need a completed Task, you only do this once.
– i3arnon
Aug 7 '15 at 9:...
How to force the browser to reload cached CSS/JS files?
...ate suggestions from John Millikin and da5id. This solution is written in PHP, but should be easily adapted to other languages.
Update 2: Incorporating comments from Nick Johnson that the original .htaccess regex can cause problems with files like json-1.3.js. Solution is to only rewrite if there ...
Why use iterators instead of array indices?
... end+1(!). For streams the iterator model is just surreal -- an imaginary token that does not exist. Likewise for linked lists. The paradigm only makes sense for arrays, and then not much. Why do I need two iterator object, not just one...
– Tuntable
Jan 21...