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Overloading member access operators ->, .*
I understand most operator overloading, with the exception of the member access operators -> , .* , ->* etc.
5 An...
How can I upload files asynchronously?
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With HTML5 you can make file uploads with Ajax and jQuery. Not only that, you can do file validations (name, size, and MIME type) or handle the progress event with the HTML5 progress tag (or a div). Recently I had to make a file uploader, but I didn't want to use Flash no...
Why does SIGPIPE exist?
From my understanding, SIGPIPE can only occur as the result of a write() , which can (and does) return -1 and set errno to EPIPE ... So why do we have the extra overhead of a signal? Every time I work with pipes I ignore SIGPIPE and have never felt any pain as a result, am I missing somethin...
What does the caret operator (^) in Python do?
I ran across the caret operator in python today and trying it out, I got the following output:
5 Answers
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PHP Regex to check date is in YYYY-MM-DD format
...t answer? This returns true for a number of invalid dates like 2016-02-30 and 2016-09-31
– Graham
Oct 11 '16 at 14:35
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Should I prefer pointers or references in member data?
..., as you mention, preventing the implementation of an assignment operator) and provide no benefits to what the class can provide.
Example problems:
you are forced to initialise the reference in each constructor's initialiser list: there's no way to factor out this initialisation into another func...
Should a return statement be inside or outside a lock?
... that in some place in my code I have the return statement inside the lock and sometime outside. Which one is the best?
9 A...
Canary release strategy vs. Blue/Green
My understanding of a canary release is that it's a partial release to a subset of production nodes with sticky sessions turned on. That way you can control and minimize the number of users/customers that get impacted if you end up releasing a bad bug.
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Regular expression for letters, numbers and - _
...iteral .
References
regular-expressions.info/Anchors, Character Classes and Repetition
In PHP
Here's a snippet to show how you can use this pattern:
<?php
$arr = array(
'screen123.css',
'screen-new-file.css',
'screen_new.js',
'screen new file.css'
);
foreach ($arr as $s) {
if...
Difference between “change” and “input” event for an `input` element
Can someone tell me what the difference between the change and input events is?
4 Answers
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