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Are nested try/except blocks in python a good programming practice?
...EAFP.
Personally, I prefer to avoid nesting when it's not necessary:
def __getattribute__(self, item):
try:
return object.__getattribute__(item)
except AttributeError:
pass # fallback to dict
try:
return self.dict[item]
except KeyError:
raise Attrib...
Why does using an Underscore character in a LIKE filter give me all the results?
...
Modify your WHERE condition like this:
WHERE mycolumn LIKE '%\_%' ESCAPE '\'
This is one of the ways in which Oracle supports escape characters. Here you define the escape character with the escape keyword. For details see this link on Oracle Docs.
The '_' and '%' are wildcards in a ...
lodash multi-column sortBy descending
...ash 3.5.0 you can use sortByOrder (renamed orderBy in v4.3.0):
var data = _.sortByOrder(array_of_objects, ['type','name'], [true, false]);
Since version 3.10.0 you can even use standard semantics for ordering (asc, desc):
var data = _.sortByOrder(array_of_objects, ['type','name'], ['asc', 'desc'...
Programmatically Request Access to Contacts
... // First time access has been granted, add the contact
[self _addContactToAddressBook];
} else {
// User denied access
// Display an alert telling user the contact could not be added
}
});
}
else if (ABAddressBookGetAuthorizationStatus() == kABAu...
What is time_t ultimately a typedef to?
...
The time_t Wikipedia article article sheds some light on this. The bottom line is that the type of time_t is not guaranteed in the C specification.
The time_t datatype is a data type in
the ISO C library defined for storing
s...
When I catch an exception, how do I get the type, file, and line number?
...y:
raise NotImplementedError("No error")
except Exception as e:
exc_type, exc_obj, exc_tb = sys.exc_info()
fname = os.path.split(exc_tb.tb_frame.f_code.co_filename)[1]
print(exc_type, fname, exc_tb.tb_lineno)
...
How to compare type of an object in Python?
...
isinstance works:
if isinstance(obj, MyClass): do_foo(obj)
but, keep in mind: if it looks like a duck, and if it sounds like a duck, it is a duck.
EDIT: For the None type, you can simply do:
if obj is None: obj = MyClass()
...
How to calculate a time difference in C++
...
See std::clock() function.
const clock_t begin_time = clock();
// do something
std::cout << float( clock () - begin_time ) / CLOCKS_PER_SEC;
If you want calculate execution time for self ( not for user ), it is better to do this in clock ticks ( not seco...
Is bool a native C type?
...ent C - C99, but not in C89/90.
In C99 the native type is actually called _Bool, while bool is a standard library macro defined in stdbool.h (which expectedly resolves to _Bool). Objects of type _Bool hold either 0 or 1, while true and false are also macros from stdbool.h.
Note, BTW, that this imp...
Check OS version in Swift?
...OS8 = floor(NSFoundationVersionNumber) > floor(NSFoundationVersionNumber_iOS_7_1)
let iOS7 = floor(NSFoundationVersionNumber) <= floor(NSFoundationVersionNumber_iOS_7_1)
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