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What is null in Java?
...s an instanceof.
15.20.2 Type Comparison Operator instanceof
RelationalExpression:
RelationalExpression instanceof ReferenceType
At run time, the result of the instanceof operator is true if the value of the RelationalExpression is not null and the reference could be cast to the Referen...
Is nested function a good approach when required by only one function? [closed]
...
>>> def sum(x, y):
... def do_it():
... return x + y
... return do_it
...
>>> a = sum(1, 3)
>>> a
<function do_it at 0xb772b304>
>>> a()
4
Is this what you were looking for? It's ca...
What is the “->” PHP operator called and how do you say it when reading code out loud? [closed]
...
Note that the lexical token is not always what that token is usually referred to. For example, ::'s name is the "scope resolution operator" but is listed in that article as T_DOUBLE_COLON. I'll +1 to you when I get some more votes :)
...
open read and close a file in 1 line of code
...n will do it automatically either during garbage collection or at program exit. But as @delnan noted, it's better practice to explicitly close it for various reasons.
So, what you can do to keep it short, simple and explicit:
with open('pagehead.section.htm','r') as f:
output = f.read()
Now ...
How can I configure Logback to log different levels for a logger to different destinations?
...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.StdOutFilter" />
...
</appender>
<appender name="stderr" cl...
How to filter files when using scp to copy dir recursively?
...ably recommend using something like rsync for this due to its include and exclude flags, e.g:-
rsync -rav -e ssh --include '*/' --include='*.class' --exclude='*' \
server:/usr/some/unknown/number/of/sub/folders/ \
/usr/project/backup/some/unknown/number/of/sub/folders/
Some other useful flags:
...
Order data frame rows according to vector with specific order
...ered according to a "target" vector as the one I implemented in the short example below?
5 Answers
...
How do I find where JDK is installed on my windows machine?
...
If you are using Linux/Unix/Mac OS X:
Try this:
$ which java
Should output the exact location.
After that, you can set JAVA_HOME environment variable yourself.
In my computer (Mac OS X - Snow Leopard):
$ which java
/usr/bin/java
$ ls -l /u...
What is uint_fast32_t and why should it be used instead of the regular int and uint32_t?
...may not be sufficient for your application.
uint32_t is not guaranteed to exist. It's an optional typedef that the implementation must provide iff it has an unsigned integer type of exactly 32-bits. Some have a 9-bit bytes for example, so they don't have a uint32_t.
uint_fast32_t states your intent ...
“Invalid JSON primitive” in Ajax processing
I am getting an error in an ajax call from jQuery.
12 Answers
12
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