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How to access command line parameters?
...s the command line arguments by using the std::env::args or std::env::args_os functions. Both functions return an iterator over the arguments. The former iterates over Strings (that are easy to work with) but panics if one of the arguments is not valid unicode. The latter iterates over OsStrings and...
open() in Python does not create a file if it doesn't exist
...ating (note that 'w+' truncates the file).
– SilentGhost
Jun 3 '10 at 15:16
4
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How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...
How do I uninstall nodejs installed from pkg (Mac OS X)?
...g to do what you want. The script was written against older versions of macOS and Node.js so may require updates.
– nicerobot
Aug 19 '19 at 13:17
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Understanding the Event Loop
... queue, and runs it.
A key thing to understand is that node relies on the OS for most of the heavy lifting. So incoming network requests are actually tracked by the OS itself and when node is ready to handle one it just uses a system call to ask the OS for a network request with data ready to be pr...
Get users by name property using Firebase
...:
Write to Firebase with a unique, known key:
ref.child('users').child('123').set({ "first_name": "rob", "age": 28 })
Append to lists with an auto-generated key that will automatically sort by time written:
ref.child('users').push({ "first_name": "rob", "age": 28 })
Listen for changes in data ...
Passing command line arguments from Maven as properties in pom.xml
Is it possible to pass arguments from command line to properties in pom.xml file ?
for example I run mvn ... argument
5 ...
Mac OS X - EnvironmentError: mysql_config not found
...-Python (or pip3 install mysqlclient if using python 3)
If you did all those steps in the same order, and you still got an error, read on to the end, if, however, you did not follow these exact steps try, following them from the very beginning.
So, you followed the steps, and you're still geting ...
Dynamic instantiation from string name of a class in dynamically imported module?
...
@jpennell you should post that as an answer, it's often more useful to be able to directly use the string returned by obj.__module__
– Anentropic
Aug 22 '14 at 12:42
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Is JavaScript an untyped language?
...licit compiler interjection, the instruction will error during run-time.
"12345" * 1 === 12345 // string * number => number
Strongly typed means there is a compiler, and it wants you an explicit cast from string to integer.
(int) "12345" * 1 === 12345
In either case, some compiler's featur...