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Argparse optional positional arguments?
...gt; parser.add_argument('-v', action='store_true')
_StoreTrueAction(option_strings=['-v'], dest='v', nargs=0, const=True, default=False, type=None, choices=None, help=None, metavar=None)
>>> parser.add_argument('dir', nargs='?', default=os.getcwd())
_StoreAction(option_strings=[], dest='dir...
Why does GitHub recommend HTTPS over SSH?
... accessible using HTTPS than SSH.
In my view SSH keys are worth the little extra work in creating them
SSH Keys do not provide access to your GitHub account, so your account cannot be hijacked if your key is stolen.
Using a strong keyphrase with your SSH key limits any misuse, even if your key get...
What is a 'thunk'?
...re's function. The thunk here is effectively supplying one or more hidden extra arguments to the function that are not provided by the call site.
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iphone Core Data Unresolved error while saving
... // If Cocoa generated the error...
if ([[error domain] isEqualToString:@"NSCocoaErrorDomain"]) {
// ...check whether there's an NSDetailedErrors array
NSDictionary *userInfo = [error userInfo];
if ([userInfo valueForKey:@"NSDetailedErrors"] ...
Is there a “standard” format for command line/shell help text?
...tion that would be in a manpage as part of the program --help output. This extra will include longer descriptions, concepts explained, usage samples, known limitations and bugs, how to report a bug, and possibly a 'see also' section for related commands.
I hope this helps.
...
Subtract two variables in Bash
...
You just need a little extra whitespace around the minus sign, and backticks:
COUNT=`expr $FIRSTV - $SECONDV`
Be aware of the exit status:
The exit status is 0 if EXPRESSION is neither null nor 0, 1 if EXPRESSION is null or 0.
Keep this in min...
Syntax error on print with Python 3 [duplicate]
Why do I receive a syntax error when printing a string in Python 3?
3 Answers
3
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Difference between one-to-many and many-to-one relationship
...ually add any columns to the table that is the "one". The Customer has no extra columns which describe the relationship with Order. In fact the Customer might also have a one-to-many relationship with ShippingAddress and SalesCall tables and yet have no additional columns added to the Customer tab...
What is the “assert” function?
...e <assert.h>
void analyze (char *, int);
int main(void)
{
char *string = "ABC";
int length = 3;
analyze(string, length);
printf("The string %s is not null or empty, "
"and has length %d \n", string, length);
}
void analyze(char *string, int length)
{
assert(string ...
Check if my app has a new version on AppStore
...Dictionary* infoDictionary = [[NSBundle mainBundle] infoDictionary];
NSString* appID = infoDictionary[@"CFBundleIdentifier"];
NSURL* url = [NSURL URLWithString:[NSString stringWithFormat:@"http://itunes.apple.com/lookup?bundleId=%@", appID]];
NSData* data = [NSData dataWithContentsOfURL:...