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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...
How to print the contents of RDD?
...save in a single file, you can coalesce you RDD into one partition before calling saveAsTextFile, but again this may cause issues. I think the best option is to write in multiple files in HDFS, then use hdfs dfs --getmerge in order to merge the files
– Oussama
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How do I mock an open used in a with statement (using the Mock framework in Python)?
...ager (from the examples page in the mock documentation):
>>> open_name = '%s.open' % __name__
>>> with patch(open_name, create=True) as mock_open:
... mock_open.return_value = MagicMock(spec=file)
...
... with open('/some/path', 'w') as f:
... f.write('something')
...
Asp.NET Web API - 405 - HTTP verb used to access this page is not allowed - how to set handler mappi
...
Common cause for this error is WebDAV. Make sure you uninstall it.
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How is null + true a string?
...t's walk through this in turn.
X is the null type here - or not a type at all, if you want to think of it that way. It's not providing any candidates. Y is bool, which doesn't provide any user-defined + operators. So the first step finds no user-defined operators.
The compiler then moves on to the...
os.path.dirname(__file__) returns empty
...get the dirname of the absolute path, use
os.path.dirname(os.path.abspath(__file__))
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How can I reference a commit in an issue comment on GitHub?
...linator/commit/f36e3c5b3aba23a6c9cf7c01e7485028a23c3811
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Account name | Hash of revision
Project...
node.js fs.readdir recursive directory search
... search using fs.readdir? I realise that we could introduce recursion and call the read directory function with the next directory to read, but am a little worried about it not being async...
...
Forward declaring an enum in C++
...can't know the storage required for the enum variable. C++ Compiler's are allowed to specify the actual storage space based on the size necessary to contain all the values specified. If all that is visible is the forward declaration, the translation unit can't know what storage size will have been...
How to make lists contain only distinct element in Python? [duplicate]
...ving
return list(_f(seq, idfun))
def _f(seq, idfun=None):
''' Originally proposed by Andrew Dalke '''
seen = set()
if idfun is None:
for x in seq:
if x not in seen:
seen.add(x)
yield x
else:
for x in seq:
x = idfun(x)
if x not in seen:
s...