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'AND' vs '&&' as operator
...
If you use AND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the ...
Odd behavior when Java converts int to byte?
...+ unsignedByte);
Would print out: "Signed: -1 Unsigned: 255"
What's actually happening here?
We are using bitwise AND to mask all of the extraneous sign bits (the 1's to the left of the least significant 8 bits.)
When an int is converted into a byte, Java chops-off the left-most 24 bits
111111...
Can I restore a single table from a full mysql mysqldump file?
I have a mysqldump backup of my mysql database consisting of all of our tables which is about 440 megs. I want to restore the contents of just one of the tables from the mysqldump. Is this possible? Theoretically, I could just cut out the section that rebuilds the table I want but I don't even know ...
Does JavaScript have a built in stringbuilder class?
... strings with the + or += operator are extremely slow on IE. This is especially true for IE6. On modern browsers += is usually just as fast as array joins.
When I have to do lots of string concatenations I usually fill an array and don't use a string builder class:
var html = [];
html.push(
"&l...
CSS: How to position two elements on top of each other, without specifying a height?
...exactly on top of each other. However, when I do that, the formatting gets all screwed up because the containing DIV acts like there is no height. I think this is the expected behavior with position:absolute but I need to find a way to position these two elements on top of each other and have the ...
How to join two JavaScript Objects, without using JQUERY [duplicate]
... merge them and crete a single json object.
The resultant json should have all the values from obj2 and the values from obj1 which is not present in obj2.
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Difference between local and global indexes in DynamoDB
...ndary index is
considered "global" because queries on the index can span all of the
data in a table, across all partitions.
Local secondary index — an index that has the same hash key as the
table, but a different range key. A local secondary index is "local"
in the sense that every p...
Why are regular expressions so controversial? [closed]
...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs.
– Pacerier
Dec 1 '15 at 21:53
...
Can local storage ever be considered secure? [closed]
... with cryptography in client-side (browser) javascript are detailed below. All but one of these concerns does not apply to the WebCrypto API, which is now reasonably well supported.
For an offline app, you must still design and implement a secure keystore.
Aside: If you are using Node.js, use the ...
Jquery - How to make $.post() use contentType=application/json?
... to
1.Modify the source to make $.post always use JSON data type as it really is just a shortcut for a pre configured $.ajax call
Or
2.Define your own utility function that is a shortcut for the $.ajax configuration you want to use
Or
3.You could overwrite the $.post function with your own i...