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Which is faster : if (bool) or if(int)?
...helps to illuminate that when choosing a variable type, you're choosing it for two potentially competing purposes, storage space vs. computational performance.
– Triynko
Apr 27 '11 at 18:20
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Read a file in Node.js
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this code doesn't seem to be working for me, i still get the same error
– aiden87
Mar 13 '16 at 10:44
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Shell script while read line loop stops after the first line
...ly, a workaround which isn't specific to ssh is to redirect standard input for any command which might otherwise consume the while loop's input.
while read -r LINE; do
let count++
echo "$count $LINE"
sh ./do_work.sh "$LINE" </dev/null
done < "$FILENAME"
The addition of </dev/nul...
How do I loop through or enumerate a JavaScript object?
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You can use the for-in loop as shown by others. However, you also have to make sure that the key you get is an actual property of an object, and doesn't come from the prototype.
Here is the snippet:
var p = {
"p1": "value1",
"...
Resize fields in Django Admin
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You should use ModelAdmin.formfield_overrides.
It is quite easy - in admin.py, define:
from django.forms import TextInput, Textarea
from django.db import models
class YourModelAdmin(admin.ModelAdmin):
formfield_overrides = {
models.Char...
Execution time of C program
...which could be anywhere from 1 second to several minutes). I have searched for answers, but they all seem to suggest using the clock() function, which then involves calculating the number of clocks the program took divided by the Clocks_per_second value.
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Rails I18n validation deprecation warning
...clude the following line inside the Rails::Application body
config.i18n.enforce_available_locales = true
The possible values are:
false: if you
want to skip the locale validation
don't care about locales
true: if you
want the application to raise an error if an invalid locale is passed (or...
Double Negation in C++
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@lzprgmr: explicit cast causes a "performance warning" on MSVC. Using !! or !=0 solves the problem, and among the two I find the former cleaner (since it will work on a greater amount of types). Also I agree that there is no reason to use either in the code in q...
Does C# have extension properties?
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For the moment it is still not supported out of the box by Roslyn compiler ...
Until now, the extension properties were not seen as valuable enough to be included in the previous versions of C# standard. C# 7 and C# 8.0 have...
Python exit commands - why so many and when should each be used?
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Let me give some information on them:
quit() simply raises the SystemExit exception.
Furthermore, if you print it, it will give a message:
>>> print (quit)
Use quit() or Ctrl-Z plus Return to exit
>>>
This functionalit...