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How do exceptions work (behind the scenes) in c++
...
Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (throwit)
throw MyExceptio...
How do I filter ForeignKey choices in a Django ModelForm?
...yset attribute. Depends on how your form is built. If you build an explicit form, you'll have fields named directly.
form.rate.queryset = Rate.objects.filter(company_id=the_company.id)
If you take the default ModelForm object, form.fields["rate"].queryset = ...
This is done explicitly in the ...
Asking the user for input until they give a valid response
I am writing a program that accepts an input from the user.
21 Answers
21
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Length of generator output [duplicate]
Python provides a nice method for getting length of an eager iterable, len(x) that is. But I couldn't find anything similar for lazy iterables represented by generator comprehensions and functions. Of course, it is not hard to write something like:
...
Dynamically set local variable [duplicate]
...ther answers already posted you cannot modify locals() directly and expect it to work.
>>> def foo():
lcl = locals()
lcl['xyz'] = 42
print(xyz)
>>> foo()
Traceback (most recent call last):
File "<pyshell#6>", line 1, in <module>
foo()
File "<p...
Instance attribute attribute_name defined outside __init__
I split up my class constructor by letting it call multiple functions, like this:
6 Answers
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How can I create a copy of an object in Python?
...follow
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edited Dec 14 '18 at 15:35
answered Jan 25 '11 at 13:49
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What is the advantage of GCC's __builtin_expect in if else statements?
...expect(x, 0)) {
foo();
...
} else {
bar();
...
}
I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes ...
How to change a module variable from another module?
Suppose I have a package named bar , and it contains bar.py :
3 Answers
3
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How can I reference a commit in an issue comment on GitHub?
I find a lot of answers on how to reference a GitHub issue in a git commit (using the #xxx notation).
I'd like to reference a commit in my comment, generating a link to the commit details page?
...