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Getter and Setter?
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That's not really setter and getter. Typically I need for each property different implementation of getter!
– sumid
Feb 16 '13 at 0:59
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Are types like uint32, int32, uint64, int64 defined in any stdlib header?
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This answer is wrong. All of the above are only available if an exact width type of that size (no padding) exists in the implementation. Even if not, however, the types int_leastNN_t and uint_leastNN_t for NN 8, 16, 32, and 64 must always exist. C...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
Timeout on a function call
I'm calling a function in Python which I know may stall and force me to restart the script.
18 Answers
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How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Why do we always prefer using parameters in SQL statements?
...uld be
SELECT empSalary from employee where salary = 0 or 1=1
whereby all empSalaries would be returned.
Further, a user could perform far worse commands against your database, including deleting it If they wrote 0; Drop Table employee:
SELECT empSalary from employee where salary = 0; Drop Ta...
Programmatically Request Access to Contacts
...ss to the address book must be granted before it can be access programmatically. Here is what I ended up doing.
#import <AddressBookUI/AddressBookUI.h>
// Request authorization to Address Book
ABAddressBookRef addressBookRef = ABAddressBookCreateWithOptions(NULL, NULL);
if (ABAddress...
How to convert vector to array
...making a pointer that points to the actual array the vector is using internally. If you want to copy GMan's answer explains how
– Michael Mrozek
May 27 '10 at 17:22
4
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When is “i += x” different from “i = i + x” in Python?
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This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...