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How do I pass command line arguments to a Node.js program?
...
You can also access a single argument when you know its position: process.argv[n] where n is the zero-based index
– Luca Steeb
Feb 1 '15 at 15:12
...
Python None comparison: should I use “is” or ==?
... when you want to check against an object's identity (e.g. checking to see if var is None). Use == when you want to check equality (e.g. Is var equal to 3?).
Explanation:
You can have custom classes where my_var == None will return True
e.g:
class Negator(object):
def __eq__(self,other):
...
✔ Checkmark selected row in UITableViewCell
...
What if I want only the checkmark and want to deselect the row after a selection?
– gyozo kudor
Jan 8 '15 at 8:59
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How do you round a floating point number in Perl?
... can have serious implications, and
the rounding method used should be specified precisely. In these
cases, it probably pays not to trust whichever system rounding is being
used by Perl, but to instead implement the rounding function you need
yourself.
To see why, notice how you'll still have an i...
Remove a string from the beginning of a string
... form, without regex:
$prefix = 'bla_';
$str = 'bla_string_bla_bla_bla';
if (substr($str, 0, strlen($prefix)) == $prefix) {
$str = substr($str, strlen($prefix));
}
Takes: 0.0369 ms (0.000,036,954 seconds)
And with:
$prefix = 'bla_';
$str = 'bla_string_bla_bla_bla';
$str = preg_replace('/^...
How can Perl's print add a newline by default?
...
The real danger comes from the fact that all code will now add newlines, even code in other people's modules that weren't expecting it. Imagine networking code that would have sent the message "helo\r\n" that now sends "helo\r\n\n".
– Chas. Owens
...
Hidden features of Ruby
Continuing the "Hidden features of ..." meme, let's share the lesser-known but useful features of Ruby programming language.
...
Number of elements in a javascript object
...ntProperties(obj) {
var count = 0;
for(var prop in obj) {
if(obj.hasOwnProperty(prop))
++count;
}
return count;
}
In case of ECMAScript 5 capable implementations, this can also be written as (Kudos to Avi Flax)
function countProperties(obj) {
return Objec...
Remove local git tags that are no longer on the remote repository
... This must be my favourite git answer on StackOverflow. It combines knowledge, simplicity and trickery an explains everything. Great
– tymtam
Nov 30 '11 at 8:12
26
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No internet on Android emulator - why and how to fix? [closed]
...ator command line solved the issue for me. Android had no internet before, now it has. Running on Win10. I'm puzzled why that command line argument was necessary though?
– mipnw
Apr 1 '18 at 3:18
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