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Difference between \w and \b regular expression meta characters
...chor like the caret and the dollar sign. It matches at a position that is called a "word boundary". This match is zero-length.
There are three different positions that qualify as word boundaries:
Before the first character in the string, if the first character is
a word character.
After the last ...
How to import module when module name has a '-' dash or hyphen in it?
...appens with sys.modules, you don't need it to import itself), just getting all of the file's globals into your own scope, you can use execfile
# contents of foo-bar.py
baz = 'quux'
>>> execfile('foo-bar.py')
>>> baz
'quux'
>>>
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How do you echo a 4-digit Unicode character in Bash?
...d like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .
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Do I set properties to nil in dealloc when using ARC?
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Short answer: no, you do not have to nil out properties in dealloc under ARC.
Long answer: You should never nil out properties in dealloc, even in manual memory management.
In MRR, you should release your ivars. Nilling out properties means calling setters, which may invoke code that...
Why can't C compilers rearrange struct members to eliminate alignment padding? [duplicate]
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There are multiple reasons why the C compiler cannot automatically reorder the fields:
The C compiler doesn't know whether the struct represents the memory structure of objects beyond the current compilation unit (for example: a foreign library, a file on disc, network data, CPU page ...
What should my Objective-C singleton look like? [closed]
My singleton accessor method is usually some variant of:
26 Answers
26
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How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
How do I find the duplicates in a list and create another list with them?
... @Hugo, to see the list of duplicates, we just need to create a new list called dup and add an else statement. For example: dup = [] else: dup.append(x)
– Chris Nielsen
Apr 29 '16 at 16:45
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Greenlet Vs. Threads
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Greenlets provide concurrency but not parallelism. Concurrency is when code can run independently of other code. Parallelism is the execution of concurrent code simultaneously. Parallelism is particularly useful when there's a lot of work to be done in userspace, an...
Changing password with Oracle SQL Developer
... answered Feb 4 '13 at 22:21
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