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Forced naming of parameters in Python
...ed.
Cons:
Checking occurs during run-time, not compile-time.
Use of an extra parameter (though not argument) and an additional check. Small performance degradation respect to regular functions.
Functionality is a hack without direct support by the language (see note below).
When calling the fun...
How to 'insert if not exists' in MySQL?
...ique($table, $vars)
{
if (count($vars)) {
$table = mysql_real_escape_string($table);
$vars = array_map('mysql_real_escape_string', $vars);
$req = "INSERT INTO `$table` (`". join('`, `', array_keys($vars)) ."`) ";
$req .= "SELECT '". join("', '", $vars) ."' FROM DUAL ";
$req .=...
When to use Cast() and Oftype() in Linq
...T
for example:
object[] objs = new object[] { "12345", 12 };
objs.Cast<string>().ToArray(); //throws InvalidCastException
objs.OfType<string>().ToArray(); //return { "12345" }
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How can I generate an ObjectId with mongoose?
...ew mongoose.mongo.ObjectId('56cb91bdc3464f14678934ca');
// or leave the id string blank to generate an id with a new hex identifier
var newId2 = new mongoose.mongo.ObjectId();
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Convert Base64 string to an image file? [duplicate]
I am trying to convert my base64 image string to an image file. This is my Base64 string:
8 Answers
...
How to serialize Joda DateTime with Jackson JSON processor?
...2)
throws IOException, JsonProcessingException {
gen.writeString(formatter.print(value));
}
}
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Is there a difference between “==” and “is”?
...0 is 10**3
False
>>> 1000 == 10**3
True
The same holds true for string literals:
>>> "a" is "a"
True
>>> "aa" is "a" * 2
True
>>> x = "a"
>>> "aa" is x * 2
False
>>> "aa" is intern(x*2)
True
Please see this question as well.
...
Checking for an empty field with MySQL
...
An empty field can be either an empty string or a NULL.
To handle both, use:
email > ''
which can benefit from the range access if you have lots of empty email record (both types) in your table.
...
fastest MD5 Implementation in JavaScript
...mple interface.
So if you want to calculate the MD5 hash of your password string then do as follows:
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.9-1/core.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.9-1/md5.js"></script&...
Choosing Java vs Python on Google App Engine
...anced and better developed than the Java runtime -- the former has had one extra year to develop and mature, after all.
How things will proceed going forward is of course hard to predict -- demand is probably stronger on the Java side (especially since it's not just about Java, but other languages ...