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Is null an Object?
...ype null
According to OpenJDKs 12.0.1 javac it is:
true.toString(); // error: boolean cannot be dereferenced
null.toString(); // error: <null> cannot be dereferenced
Where the angle brackets imply that null is of an other than a primitive type. And according to JLS 4.1:
There are tw...
Getting Chrome to accept self-signed localhost certificate
... self-signed certs worked fine in the past but suddenly started generating errors in Chrome 58, this is why.
So whatever method you are using to generate your self-signed cert (or cert signed by a self-signed CA), ensure that the server's cert contains a subjectAltName with the proper DNS and/or IP...
UIRefreshControl on UICollectionView only works if the collection fills the height of the container
...
Const gives an error of undefined variable. if someone encounters the same situation just replace it with UIColor.whiteColor() or whatever color you like.
– Faisal
May 13 '16 at 5:04
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Is it OK to leave a channel open?
...e it's nondeterministic. Most common related gotcha is too many open files error. You keep opening files... You expect GC to do so... You don't run out of memory (therefore GC doesn't kick in)... You run out of file descriptors at the OS level. OS kills the process :)
– Pijusn
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How should one use std::optional?
...archy, instead of passing around some "phantom" value "assumed" to have a "error" meaning.
– Luis Machuca
Oct 3 '13 at 16:35
1
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When do I need to use a semicolon vs a slash in Oracle SQL?
...gt; drop table foo;
Table dropped.
SQL> /
drop table foo
*
ERROR at line 1:
ORA-00942: table or view does not exist
In this case one actually notices the error.
But assuming there is a SQL script like this:
drop table foo;
/
And this is run from within SQL*Plus then this wil...
How can I read a text file without locking it?
... Seems to work when reading data. When writing the locked file error comes up.
– webzy
Feb 8 '16 at 9:00
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Execute Python script via crontab
...e the file appears a message: "/tmp/crontab.JTQ0My/crontab":22: bad minute errors in crontab file, can't install. Do you want to retry the same edit? (y/n)" if I type "y", I've returned to file edit. And if I type "n" the file is not saved. I add this line at last line of the file: "/1 * * * * /usr...
How do I remove/delete a virtualenv?
...em to set up the environment in the first place, which would usually be an error.
– tripleee
Apr 13 '19 at 14:40
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Is there a max array length limit in C++?
...e factors as external disturbances and thus as possible sources of runtime errors, and to carefully check&react to memory-allocation related errors in your program code.
So finally: while C++ does not impose any limits, you still have to check for adverse memory-related conditions when running y...