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remove None value from a list without removing the 0 value
... - it's just for scientific purposes)
>>> from operator import is_not
>>> from functools import partial
>>> L = [0, 23, 234, 89, None, 0, 35, 9]
>>> filter(partial(is_not, None), L)
[0, 23, 234, 89, 0, 35, 9]
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How to query MongoDB with “like”?
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Actually, it depends. If the query doesn't use an index, and must do a table scan, then it can certainly be expensive. If you're doing a 'starts with' regex query, then that can use an index. Best to run an explain() to see what'...
How to remove k__BackingField from json when Deserialize
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Automatic Property syntax is actually not recommended if the class can be used in serialization. Reason being the backing field is generated by compiler which can be different each time code is compiled. This can cause incompatibility issues even if no chang...
Create list of single item repeated N times
I want to create a series of lists, all of varying lengths. Each list will contain the same element e , repeated n times (where n = length of the list).
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Get object by id()? [duplicate]
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@HamidFzM No, not really. If I have an ID, I maybe don't even know whether the object still exists or not.
– glglgl
Jul 21 '14 at 8:13
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PowerShell equivalent to grep -f
...h/2011/03/powershell-search-for-string-or-grep-for-powershell/
But essentially it is:
Select-String -Path "C:\file\Path\*.txt" -Pattern "^Enter REGEX Here$"
This gives a directory file search (*or you can just specify a file) and a file-content search all in one line of PowerShell, very similar ...
assertEquals vs. assertEqual in python
...as been deprecated as well:
Method Name | Deprecated alias(es)
_________________________________________________________
assertEqual() | failUnlessEqual, assertEquals
From 25.3.7.1.1. Deprecated aliases
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Getting a random value from a JavaScript array
... @SapphireSun this is correct. Note the Math.floor(Math.random(...)) call, which rounds down.
– ashes999
Jan 19 '14 at 12:43
34
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What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
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