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Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
...
Quickly find whether a value is present in a C array?
...ned assembly language. I tend to take the path of least resistance - for small routines like this, I just write asm code and have a good idea how many cycles it will take to execute. You may be able to fiddle with the C code and get the compiler to generate good output, but you may end up wasting lo...
undefined reference to `__android_log_print'
...sary. Please accept the other answer instead.
– Jeff Allen
Jun 21 '13 at 11:23
5
If using the new...
Adding a new value to an existing ENUM Type
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It's worth mentioning that this can all be done in a single transaction, so it's mostly safe to do it in a production database.
– David Leppik
Jul 8 '11 at 20:41
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Adding git branch on the Bash command prompt
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git 1.9.3 or later: use __git_ps1
Git provides a shell script called git-prompt.sh, which includes a function __git_ps1 that
prints text to add to bash PS1 prompt (includes branch name)
Its most basic usage is:
$ __git_ps1
(master)
It also takes an optional format string:
$ __g...
How to exit in Node.js
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Call the global process object's exit method:
process.exit()
From the docs:
process.exit([exitcode])
Ends the process with the specified code. If omitted, exit uses the 'success' code 0.
To exit with a 'failure' code:
proces...
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...
Catch a thread's exception in the caller thread in Python
I'm very new to Python and multithreaded programming in general. Basically, I have a script that will copy files to another location. I would like this to be placed in another thread so I can output .... to indicate that the script is still running.
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Getting a map() to return a list in Python 3.x
...ases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even convert it to a list, because you can still iterate over the map object like so:
# Prints "ABCD"
for ch in map(chr,[65,66,67,68]):
prin...
jQuery: Select data attributes that aren't empty?
I'm trying to select all elements that have a data-go-to attribute that is not empty.
11 Answers
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