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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Creating a dynamic choice field
...ted May 27 '16 at 18:04
Tim Tisdall
8,27033 gold badges4141 silver badges6767 bronze badges
answered Aug 6 '10 at 2:17
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String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
Elegant Python function to convert CamelCase to snake_case?
...
name = pattern.sub('_', name).lower()
To handle more advanced cases specially (this is not reversible anymore):
def camel_to_snake(name):
name = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', name)
return re.sub('([a-z0-9])([A-Z])', r'\1_\2', name).lower()
print(camel_to_snake('camel2_camel2_case')) #...
Capturing Groups From a Grep RegEx
...egex="[0-9]+_([a-z]+)_[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
...
Truncating all tables in a Postgres database
I regularly need to delete all the data from my PostgreSQL database before a rebuild. How would I do this directly in SQL?
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What is the best project structure for a Python application? [closed]
...l architecture of your application.
/foo
/bar
/baz
I recommend putting all of this under the "name-of-my-product" directory. So, if you're writing an application named quux, the directory that contains all this stuff is named /quux.
Another project's PYTHONPATH, then, can include /path/to/quu...
How do I import other TypeScript files?
...
You can use the --all flag with tsc on your main .ts file. The compiler figures out all the dependencies based on your reference tags and generates a single output .js file for the entire application: tsc --out app.js main.ts
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Get event listeners attached to node using addEventListener
...
You can't.
The only way to get a list of all event listeners attached to a node is to intercept the listener attachment call.
DOM4 addEventListener
Says
Append an event listener to the associated list of event listeners with type set to type, listener set to ...
Filtering for empty or NULL names in a queryset
...lias (optional) which I need to search for. So, I need a query to give me all the names that have an alias set.
7 Answers
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