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if/else in a list comprehension
...1.5, 2.3, 4.4, 5.4, 'n', 1.5, 5.1, 'a'] # Original list
# Extract non-strings from X to new list
X_non_str = [el for el in X if not isinstance(el, str)] # When using only 'if', put 'for' in the beginning
# Change all strings in X to 'b', preserve everything else as is
X_str_changed = ['b' if ...
Why does ReSharper want to use 'var' for everything?
... this very easily. There are reasons to use var, f.e. with a Dictionary<string, List<SomeType<int>>>. But if the full-type-name is not too long and you don't use new on the right side (or an explicit cast) resharper should not suggest it.
– Tim Schmelter
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Android - Set fragment id
...
You can't set a fragment's ID programmatically.
There is however, a String tag that you can set inside the FragmentTransaction which can be used to uniquely identify a Fragment.
As Aleksey pointed out, you can pass an ID to FragmentTransaction's add(int, Fragment) method. However, this does ...
How to find if a given key exists in a C++ std::map
... us std::map::contains to do that.
#include <iostream>
#include <string>
#include <map>
int main()
{
std::map<int, std::string> example = {{1, "One"}, {2, "Two"},
{3, "Three"}, {42, "Don\'t Panic!!!"}};
if(example.contains(42))...
How to pass variable number of arguments to a PHP function
...s);
This code will the output :
int 3
array
0 => int 10
1 => string 'glop' (length=4)
2 => string 'test' (length=4)
ie, 3 parameters ; exactly like iof the function was called this way :
test(10, 'glop', 'test');
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Rails migrations: self.up and self.down versus change
...d only delete this column on down
def up
add_column :users, :location, :string
User.update_all(location: 'Minsk')
end
def down
remove_column :users, :location
end
But:
You had to avoid using change method which allows to save some time. For example, if you didn’t need to update column v...
Can I grep only the first n lines of a file?
... be faster you're solution is not searching for regexps but only for fixed strings. awk '{ if ( NR <= 10 ) { if( $0 ~ "YOUR_REGEXP") { print } } else { exit; } }' textfile does.
– Zsolt Botykai
Jan 7 '12 at 10:06
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Moment.js transform to date object
...e linking and referring to is a separate issue and scenario, e.g passing a string into the moment constructor moment("12/12/2011") is where you would get that message. It has nothing to do with going from moment to date obj moment().toDate()
– btbJosh
Nov 15 '1...
How to get only time from date-time C# [closed]
...ns for this:
DateTime dt = DateTime.Parse("6/22/2009 07:00:00 AM");
dt.ToString("HH:mm"); // 07:00 // 24 hour clock // hour is always 2 digits
dt.ToString("hh:mm tt"); // 07:00 AM // 12 hour clock // hour is always 2 digits
dt.ToString("H:mm"); // 7:00 // 24 hour clock
dt.ToString("h:mm tt"); // 7...
StringLength vs MaxLength attributes ASP.NET MVC with Entity Framework EF Code First
What is the difference in behavior of [MaxLength] and [StringLength] attributes?
8 Answers
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