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What's the difference between ES6 Map and WeakMap?
...e: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap):
Keys of WeakMaps are of the type Object only. Primitive data types as
keys are not allowed (e.g. a Symbol can't be a WeakMap key).
Nor can a string, number, or boolean be used as a WeakMap key. A M...
Java Error opening registry key
...er removing the "java" executables from my system32 folder, I had to reinstall the JRE. After that, my problem was solved. Thanks for the starting point.
– dangowans
Dec 24 '13 at 18:31
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How to document thrown exceptions in c#/.net
I am currently writing a small framework that will be used internally by other developers within the company.
8 Answers
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not None test in Python [duplicate]
...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None.
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No connection could be made because the target machine actively refused it?
...
If this happens always, it literally means that the machine exists but that it has no services listening on the specified port, or there is a firewall stopping you.
If it happens occasionally - you used the word "sometimes" - and retrying succeeds, it is l...
Python: Using .format() on a Unicode-escaped string
...gt; print s
≥
>>> print "{0}".format(s)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\u2265' in position 0: ordinal not in range(128)
>>> print u"{0}".format(s)
≥
>>>
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Get the first element of each tuple in a list in Python [duplicate]
...
Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_li...
Calling a function within a Class method?
...c function newTest(){
$this->bigTest();
$this->smallTest();
}
private function bigTest(){
//Big Test Here
}
private function smallTest(){
//Small Test Here
}
public function scoreTest(){
//Scoring code here;
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Multiple inputs with same name through POST in php
... post and then access them from PHP? The idea is this: I have a form that allows the entry of an indefinite number of physical addresses along with other information. If I simply gave each of those fields the same name across several entries and submitted that data through post, would PHP be able ...
Error 1022 - Can't write; duplicate key in table
...ou can not have the same foreign key names in the database tables.
Check all your tables and all your foreign keys and avoid having two foreign keys with the same exact name.
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