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Python idiom to return first item or None
...it like:
next((x for x in blah if cond), None)
Pro: works if blah isn't indexable Con: it's unfamiliar syntax. It's useful while hacking around and filtering stuff in ipython though.
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Aren't Python strings immutable? Then why does a + “ ” + b work?
...the variable a to point at a new string "Dog eats treats". You didn't actually mutate the string "Dog". Strings are immutable, variables can point at whatever they want.
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Mark error in form using Bootstrap
...ation pass. Your code here.
}
}
View
<div class="col-md-12">
<?php
$email_error = (form_error('email') ? 'has-error has-feedback' : '');
if(!empty($email_error)){
$emailData = '<span class="help-block">'.form_error('email').'</span>';
$emailClass = $email_error;
$emailI...
Python: Is it bad form to raise exceptions within __init__?
...t have been designed with exception safety in mind, the destructor is not called if an exception is thrown in the constructor of an object (meaning that the initialization of the object is incomplete). This is often not the case in scripting languages, such as Python. For example, the following code...
Calling a class function inside of __init__
...
Call the function in this way:
self.parse_file()
You also need to define your parse_file() function like this:
def parse_file(self):
The parse_file method has to be bound to an object upon calling it (because it's not a ...
Convert string to Python class object?
... there's a class with that name in the currently defined namespace. Essentially, I want the implementation for a function which will produce this kind of result:
...
Get ID of last inserted document in a mongoDB w/ Java driver
...h MongoDB plainly auto-generates ObjectId's. However, your solution of manually creating an ObjectId does work, and thanks for this option!
– Apophenia Overload
Dec 4 '12 at 8:39
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Remove Application Insight from application on Visual Studio 2013
...d only have to remove one extension and possibly one nuget package.
Uninstall the Application Insights Tools for Visual Studio extension and remove the Application Telemetry SDK for Services nuget package. The telemetry package is installed along with Application Insights but must be removed separa...
Is there an expression for an infinite generator?
...
for x in iter(int, 1): pass
Two-argument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One va...
What is the most efficient way to deep clone an object in JavaScript?
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Native deep cloning
It's called "structured cloning", works experimentally in Node 11 and later, and hopefully will land in browsers. See this answer for more details.
Fast cloning with data loss - JSON.parse/stringify
If you do not use Dates, funct...