大约有 15,572 项符合查询结果（耗时：0.0205秒） [XML]
What is the use case of noop [:] in bash?
...o" != "1" ]
then
#echo Success
fi
Which causes bash to give a syntax error:
line 4: syntax error near unexpected token `fi'
line 4: `fi'
Bash can't have empty blocks (WTF). So you add a no-op:
if [ "$foo" != "1" ]
then
#echo Success
:
fi
or you can use the no-op to comment out...
Make sure only a single instance of a program is running
...cntl.LOCK_EX | fcntl.LOCK_NB)
already_running = False
except IOError:
already_running = True
return already_running
A lot like S.Lott's suggestion, but with the code.
share
|
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How can I configure Logback to log different levels for a logger to different destinations?
...ngs with Logback filters. The below configuration will only print warn and error messages to stderr, and everything else to stdout.
logback.xml
<appender name="stdout" class="ch.qos.logback.core.ConsoleAppender">
<target>System.out</target>
<filter class="com.foo.StdOutFil...
How to convert floats to human-readable fractions?
...x that will fit in maxden */
/* first try zero */
printf("%ld/%ld, error = %e\n", m[0][0], m[1][0],
startx - ((double) m[0][0] / (double) m[1][0]));
/* now try other possibility */
ai = (maxden - m[1][1]) / m[1][0];
m[0][0] = m[0][0] * ai + m[0][1];
m[1][0] = m[1]...
NHibernate.MappingException: No persister for: XYZ
...
This was my problem also, get the same error as in Q when doing get. When trying to query all of the objects of that type, no error, just an empty result set!
– Christoph
May 18 '15 at 15:34
...
Resolving MSB3247 - Found conflicts between different versions of the same dependent assembly
... people to actually use the Output window. Build is so much more than F5 + Error List window.
– JJS
Apr 1 '10 at 21:01
2
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Is there a tool to convert JavaScript files to TypeScript [closed]
...is just wrong. The following code is correct in JavaScript, but creates an error in TypeScript:
var data={x:5, y:6};
data.z=5;
You can get the dynamic behaviour of JavaScript by declaring data as "ambient"
var data:any={x:5, y:6};
data.z=5;
Now this will work in TypeScript, too. Nevertheless...
What is std::promise?
...n on a promise does not make sense. All exceptions are of type std::future_error, which derives from std::logic_error. First off, a description of some constraints:
A default-constructed promise is inactive. Inactive promises can die without consequence.
A promise becomes active when a future is o...
Git error: “Host Key Verification Failed” when connecting to remote repository
...
As I answered previously in Cloning git repo causes error - Host key verification failed. fatal: The remote end hung up unexpectedly, add the GitHub to the list of authorized hosts:
ssh-keyscan -t rsa github.com >> ~/.ssh/known_hosts
...
How do you test that a Python function throws an exception?
...he assertion; using @Moe's answer above for example: self.assertRaises(TypeError, mymod.myfunc). You can find a full list of the Built-in Exceptions here: docs.python.org/3/library/exceptions.html#bltin-exceptions
– Raymond Wachaga
Feb 7 '19 at 17:51
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