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The type 'string' must be a non-nullable type in order to use it as parameter T in the generic type
... the T? C# syntactic sugar with non-nullable value types such as int and Guid.
In particular, as string is a reference type, an expression of type string can already be null:
string lookMaNoText = null;
share
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...
Concurrent.futures vs Multiprocessing in Python 3
...lExecutor
def pool_factorizer_map(nums, nprocs):
# Let the executor divide the work among processes by using 'map'.
with ProcessPoolExecutor(max_workers=nprocs) as executor:
return {num:factors for num, factors in
zip(nums,
...
Are default enum values in C the same for all compilers?
...
and, this identical behavior is required by both C and C++. In C++, it's [dcl.enum]: "If the first enumerator has no initializer, the value of the corresponding constant is zero. An enumerator-definition without an initializer gives...
How to open a file for both reading and writing?
...o position 0 (i.e. the beginning). truncate() truncate the file to the provided number of bytes, i.e. removes all of the file content after the specified number of bytes. Imagine that your file has the string Hello, world and you write Bye. If you don't truncate() the content at the end will be Byel...
SortedList, SortedDictionary and Dictionary
...
I can see the proposed answers focus on performance. The article provided below does not provide anything new regarding performance, but it explains the underlying mechanisms. Also note it does not focus on the three Collection Types mentioned in the question, but addresses all the Types of th...
String.replaceAll single backslashes with double backslashes
...
To avoid this sort of trouble, you can use replace (which takes a plain string) instead of replaceAll (which takes a regular expression). You will still need to escape backslashes, but not in the wild ways required with regular exp...
How to execute PHP code from the command line?
...e Interface
If you don't, this means that maybe another command will provides the CLI SAPI. Try php-cli, maybe it's a package or a command available in your OS.
If you do see that your php command uses the CLI (Command Line Interface) SAPI (Server API), then run php -h | grep code to find out whi...
Copy multiple files in Python
...
def recursive_copy_files(source_path, destination_path, override=False):
"""
Recursive copies files from source to destination directory.
:param source_path: source directory
:param destination_path: destination directory
:param override if True all files will be o...
how to unit test file upload in django
...
Submitting files is a special case. To POST a file, you need only
provide the file field name as a key, and a file handle to the file
you wish to upload as a value. For example:
c = Client()
with open('wishlist.doc') as fp:
c.post('/customers/wishes/', {'name': 'fred', 'attachment': fp})
...
d3 axis labeling
... .attr("class", "x label")
.attr("text-anchor", "end")
.attr("x", width)
.attr("y", height - 6)
.text("income per capita, inflation-adjusted (dollars)");
And the y-axis label like this:
svg.append("text")
.attr("class", "y label")
.attr("text-anchor", "end")
.attr("y",...