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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...
Extract value of attribute node via XPath
...
With xqilla it was necessary to call xs:string. I wonder why.
– krlmlr
Jul 22 '13 at 20:00
1
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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 to access java-classes in the default-package?
...u can’t use classes in the default package from a named package.
(Technically you can, as shown in Sharique Abdullah's answer through reflection API, but classes from the unnamed namespace are not in scope in an import declaration)
Prior to J2SE 1.4 you could import classes from the default packag...
Is there any downside for using a leading double slash to inherit the protocol in a URL? i.e. src=“/
...at starting the URL with a double slash inherits the current protocol. Do all browsers support this technique?
6 Answers
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How should strace be used?
...
Strace Overview
strace can be seen as a light weight debugger. It allows a programmer / user to quickly find out how a program is interacting with the OS. It does this by monitoring system calls and signals.
Uses
Good for when you don't have source code or don't want to be bothered to real...
Metadata file … could not be found error when building projects
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Occasionally even this won't help, as noted by Nick above. In that case closing and restarting VS has always worked for me. YMMV.
– philofinfinitejest
Mar 14 '13 at 1:39
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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...
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...
PermGen elimination in JDK 8
I have installed JDK 8 and trying to run Eclipse. I am getting following warning message:
6 Answers
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