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When does static class initialization happen?
...tialized? If I never instantiate a class, but I access a static field, are ALL the static blocks and private static methods used to instantiate private static fields called (in order) at that instant?
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Should I use a class or dictionary?
...ould your __init__ code go?
Classes are for bundling related data (and usually code).
Dictionaries are for storing key-value relationships, where usually the keys are all of the same type, and all the values are also of one type. Occasionally they can be useful for bundling data when the key/attri...
Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
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Detect Chrome extension first run / update
...versions of Chrome (since Chrome 22), you can use the chrome.runtime.onInstalled event, which is much cleaner.
Example:
// Check whether new version is installed
chrome.runtime.onInstalled.addListener(function(details){
if(details.reason == "install"){
console.log("This is a first inst...
How to get value from form field in django framework?
...equest.POST) # A form bound to the POST data
if form.is_valid(): # All validation rules pass
# Process the data in form.cleaned_data
# ...
print form.cleaned_data['my_form_field_name']
return HttpResponseRedirect('/thanks/') # Redirect after ...
What would be a good docker webdev workflow?
..., fig is now deprecated in favor of docker-compose
– allan.simon
Apr 10 '15 at 20:38
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show 1 more comment
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What's the difference between ISO 8601 and RFC 3339 Date Formats?
...the web. Should I use one over the other? Is one just an extension? Do I really need to care that bad?
3 Answers
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Why do I need 'b' to encode a string with Base64?
...-z, 0-9, +, /* so it can be transmitted over channels that do not preserve all 8-bits of data, such as email.
Hence, it wants a string of 8-bit bytes. You create those in Python 3 with the b'' syntax.
If you remove the b, it becomes a string. A string is a sequence of Unicode characters. base64 ha...
How to get an array of specific “key” in multidimensional array without looping
...s = array_map(function ($ar) {return $ar['id'];}, $users);
Before(Technically php 4.0.6+), you must create an anonymous function with create_function instead:
$ids = array_map(create_function('$ar', 'return $ar["id"];'), $users);
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What is hashCode used for? Is it unique?
...r is based on the
System.Collections.IEqualityComparer interface.
Basically, hash codes exist to make hashtables possible.
Two equal objects are guaranteed to have equal hashcodes.
Two unequal objects are not guaranteed to have unequal hashcodes (that's called a collision).
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