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Is it possible to have multiple statements in a python lambda expression?
...Q. Can you put multiple statements in a lambda?
A. No. But you don't actually need to use a lambda. You can put the statements in a def instead. i.e.:
def second_lowest(l):
l.sort()
return l[1]
map(second_lowest, lst)
Q. Can you get the second lowest item from a lambda by sorting the ...
Using Default Arguments in a Function
...= "some other value";
}
code here!
}
This way, you can make a call like foo('blah', null, 'non-default y value'); and have it work as you want, where the second parameter $x still gets its default value.
With this method, passing a null value means you want the default value for one par...
Unresolved specs during Gem::Specification.reset:
...t turned out to be a missing line in the gemspec file:
$:.push File.expand_path("../lib", __FILE__)
This line is normally at the top of the file (in many of the gems I have recently been working in) and I had commented it out to see why.
...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
How to write :hover condition for a:before and a:after?
...
This depends on what you're actually trying to do.
If you simply wish to apply styles to a :before pseudo-element when the a element matches a pseudo-class, you need to write a:hover:before or a:visited:before instead. Notice the pseudo-element comes after ...
How do I install Maven with Yum?
...b/apache/maven/maven-3/3.0.5/binaries/apache-maven-3.0.5-bin.tar.gz
basically just go to the maven site. Find the version of maven you want. The file type and use the mirror for the wget statement above.
Afterwards the process is easy
Run the wget command from the dir you want to extract maven ...
How do you implement a class in C? [closed]
...se C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate the memory by assumin...
how to rotate a bitmap 90 degrees
...
In case you don't need the original bitmap, call bitmap.recycle() to be certain.
– Nick Bedford
Feb 12 '19 at 10:47
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Create directory if it does not exist
...
What will -Force actually do? The documentation says "Forces this cmdlet to create an item that writes over an existing read-only item". Will it delete an existing folder? It should be clear in this answer.
– Peter Mortensen...
How to detect if a property exists on an ExpandoObject?
...a dynamic invocation, with the case you get in the internals. More specifically, it is explicitly implemented: github.com/mono/mono/blob/master/mcs/class/dlr/Runtime/…
– Dykam
Feb 4 '15 at 18:04
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