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Print JSON parsed object?
...ve got a javascript object which has been JSON parsed using JSON.parse I now want to print the object so I can debug it (something is going wrong with the function). When I do the following...
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error: ‘NULL’ was not declared in this scope
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Now that C++11 is more generally supported by compilers, it might be worth mentioning the nullptr keyword, which is an actual keyword and doesn't require any #includes. It's also more typesafe than NULL.
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What's the difference between Perl's backticks, system, and exec?
...ere you want to fetch STDOUT, STDERR or the return code, you can use well known standard modules like IPC::Open2 and IPC::Open3.
Example:
use IPC::Open2;
my $pid = open2(\*CHLD_OUT, \*CHLD_IN, 'some', 'cmd', 'and', 'args');
waitpid( $pid, 0 );
my $child_exit_status = $? >> 8;
Finally, IPC:...
What are the differences between type() and isinstance()?
...n versions do however offer extra goodies: isinstance (and issubclass) can now mean more than just "[an instance of] a derived class" (in particular, any class can be "registered" with an ABC so that it will show as a subclass, and its instances as instances of the ABC); and ABCs can also offer extr...
UILabel sizeToFit doesn't work with autolayout ios6
...If we run the app in the simulator, sure enough, we see the same thing:
Now, let's select the UILabel in Interface Builder, and take a look at the default settings in the Size inspector:
Note the highlighted constraint above. That is the Content Hugging Priority. As Erica Sadun describes it in...
When to use MyISAM and InnoDB? [duplicate]
...resources. -- Mostly no longer true.
Full-text indexing. -- InnoDB has it now
Especially good for read-intensive (select) tables. -- Mostly no longer true.
Disk footprint is 2x-3x less than InnoDB's. -- As of Version 5.7, this is perhaps the only real advantage of MyISAM.
InnoDB:
The InnoDB st...
What is the best comment in source code you have ever encountered? [closed]
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//Dear Programmer // //Your code now runs slower now that I fixed all the bugs you //introduced. //But your optimizations sure helped.
– DevinB
Mar 6 '09 at 15:09
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How to check if an appSettings key exists?
...ager.AppSettings
if (ConfigurationManager.AppSettings[name] != null)
{
// Now do your magic..
}
or
string s = ConfigurationManager.AppSettings["myKey"];
if (!String.IsNullOrEmpty(s))
{
// Key exists
}
else
{
// Key doesn't exist
}
...
Python vs Bash - In which kind of tasks each one outruns the other performance-wise? [closed]
...lly runs a short Bash script. That script, either directly or indirectly, knows where all the files needed are and sets variables and command line parameters, finally calling the program. That's a shell's simplest use.
Linux as we know it however would hardly be Linux without the thousands of shell...
How do function pointers in C work?
... which receives 2 ints and returns an int:
int (*functionPtr)(int,int);
Now we can safely point to our function:
functionPtr = &addInt;
Now that we have a pointer to the function, let's use it:
int sum = (*functionPtr)(2, 3); // sum == 5
Passing the pointer to another function is basica...