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Using braces with dynamic variable names in PHP
...rom phpNET manual php.net/manual/ru/language.variables.variable.php $price_for_monday = 10; $price_for_tuesday = 20; $today = 'tuesday'; $price_for_today = ${ 'price_for_' . $today}; echo $price_for_today; // will return 20
– Vladimir Ch
Apr 20 '18 at 21:08
...
What are the differences between numpy arrays and matrices? Which one should I use?
...
Or just np.linalg.matrix_power(mat, n)
– Eric
Feb 28 '17 at 11:16
I...
The most accurate way to check JS object's type?
... constructor:
Native Type Ex1:
var string1 = "Test";
console.log(string1.__proto__.constructor.name);
displays:
String
Ex2:
var array1 = [];
console.log(array1.__proto__.constructor.name);
displays:
Array
Custom Classes:
function CustomClass(){
console.log("Custom Class Object C...
_DEBUG vs NDEBUG
...
Visual Studio defines _DEBUG when you specify the /MTd or /MDd option, NDEBUG disables standard-C assertions. Use them when appropriate, ie _DEBUG if you want your debugging code to be consistent with the MS CRT debugging techniques and NDEBUG if ...
“Incorrect string value” when trying to insert UTF-8 into MySQL via JDBC?
...y 4 bytes in UTF-8.
You may also have to set the server property character_set_server to utf8mb4 in the MySQL configuration file. It seems that Connector/J defaults to 3-byte Unicode otherwise:
For example, to use 4-byte UTF-8 character sets with Connector/J, configure the MySQL server with cha...
Convert hyphens to camel case (camelCase)
...and have it included in your project.
var str = 'my-hyphen-string';
str = _.camelCase(str);
// results in 'myHyphenString'
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Assignment inside lambda expression in Python
...asons. For example, we will be able to write the following:
import sys
say_hello = lambda: (
message := "Hello world",
sys.stdout.write(message + "\n")
)[-1]
say_hello()
In Python 2, it was possible to perform local assignments as a side effect of list comprehensions.
import sys
say_hell...
How to simulate target=“_blank” in JavaScript
...
<script>
window.open('http://www.example.com?ReportID=1', '_blank');
</script>
The second parameter is optional and is the name of the target window.
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How to implement a rule engine?
...;
// use a method call, e.g. 'Contains' -> 'u.Tags.Contains(some_tag)'
return Expression.Call(left, method, right);
}
}
Note that I used 'GreaterThan' instead of 'greater_than' etc. - this is because 'GreaterThan' is the .NET name for the operator, therefore we don't need any...
How to join strings in Elixir?
...u could treat it as an iolist:
["StringA", " ", "StringB"] |> IO.iodata_to_binary # "StringA StringB"
This gives you some performances boosts as you're not duplicating any of the strings in memory.
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