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When and why should I use a namedtuple instead of a dictionary? [duplicate]
...don't have keys, so hashability isn't an issue.
However, they have a more stringent restriction -- their key-equivalents, "field names", have to be strings.
Basically, if you were going to create a bunch of instances of a class like:
class Container:
def __init__(self, name, date, foo, bar):
...
How to check if a JavaScript variable is NOT undefined? [duplicate]
...could take which would also match that condition - e.g. 0, null, '' (empty string). These are called "falsy" values.
– Allan Jardine
Nov 9 '18 at 16:25
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Double negation (!!) in javascript - what is the purpose? [duplicate]
...alent to false in conditional statements:
false
null
undefined
The empty string "" (\ '')
The number 0
The number NaN
All other values are equivalent to true.
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What is the Python equivalent for a case/switch statement? [duplicate]
... @IanMobbs It's almost NEVER "proper" to put code in a constant string in quotes then eval it. 1) code doesn't get checked by your editor for validity. 2) it doesn't get optimised to bytecode at compilation. 3) you can't see syntax highlighting. 4) fiddly if you have multiple quotes - in...
Regex: ?: notation (Question mark and colon notation) [duplicate]
...e to this thread - just to build on ryanp's answer.
Assuming you have the string aaabbbccc
Regular Expression
(a)+(b)+(c)+
This would give you the following 3 groups that matched:
['a', 'b', 'c']
Regular Expression with non-capturing parenthesis
Use the ?: in the first group
(?:a)+(b)+(c)+...
How to change the icon of an Android app in Eclipse?
...android:icon="@drawable/ic_launcher" <--------
android:label="@string/app_name"
android:theme="@style/AppTheme" >
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Pass column name in data.table using variable [duplicate]
...quotes on the column names when you do it this way, because the quote()-ed string will be evaluated inside the DT[]
temp <- quote(x)
DT[ , eval(temp)]
# [1] "b" "b" "b" "a" "a"
With a single column name, the result is a vector. If you want a data.table result, or several columns, use list form...
Append file contents to the bottom of existing file in Bash [duplicate]
...
For single string, use echo like this echo "export JAVA_HOME=/usr/lib/jvm/jdk1.8.0_112" >> ~/.bashrc
– shellbye
Jan 3 '17 at 8:36
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How can we access context of an application in Robolectric?
...nner::class).
As an aside, their current guide has an example of getting string resources using:
final Context context = RuntimeEnvironment.ap
How to add hours to current time in python
...ours=9)
#datetime.datetime(2012, 12, 3, 23, 24, 31, 774118)
And then use string formatting to get the relevant pieces:
>>> '{:%H:%M:%S}'.format(nine_hours_from_now)
'23:24:31'
If you're only formatting the datetime then you can use:
>>> format(nine_hours_from_now, '%H:%M:%S')...