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Include all existing fields and add new fields to document
...s the new fields.
db.collection.aggregate([
{ "$addFields": { "custom_field": "$obj.obj_field1" } }
])
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Is it expensive to use try-catch blocks even if an exception is never thrown?
...
public class TryFinally {
public TryFinally();
Code:
0: aload_0
1: invokespecial #1 // Method java/lang/Object."<init>":()V
4: return
public static void main(java.lang.String[]) throws java.lang.Throwable;
Code:
0: new #2 ...
How do I run Python code from Sublime Text 2?
... find out where your Break key is here: http://en.wikipedia.org/wiki/Break_key.
Note: CTRL + C will NOT work.
What to do when Ctrl + Break does not work:
Go to:
Preferences -> Key Bindings - User
and paste the line below:
{"keys": ["ctrl+shift+c"], "command": "exec", "args": {"k...
Why are all fields in an interface implicitly static and final?
...a is defined by a static final field (and by convention the name uses UPPER_CASE_AND_UNDERSCORES).
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Strip HTML from strings in Python
...
from html.parser import HTMLParser
class MLStripper(HTMLParser):
def __init__(self):
super().__init__()
self.reset()
self.strict = False
self.convert_charrefs= True
self.text = StringIO()
def handle_data(self, d):
self.text.write(d)
def g...
Getting the last argument passed to a shell script
...
The simplest answer for bash 3.0 or greater is
_last=${!#} # *indirect reference* to the $# variable
# or
_last=$BASH_ARGV # official built-in (but takes more typing :)
That's it.
$ cat lastarg
#!/bin/bash
# echo the last arg given:
_last=${!#}
echo $_last
_last...
Iterating Over Dictionary Key Values Corresponding to List in Python
...ict (league) itself, or league.keys():
for team in league.keys():
runs_scored, runs_allowed = map(float, league[team])
You can also iterate over both the keys and the values at once by iterating over league.items():
for team, runs in league.items():
runs_scored, runs_allowed = map(float,...
Execution time of C program
...es calculating the number of clocks the program took divided by the Clocks_per_second value.
16 Answers
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Remove blank attributes from an Object in Javascript
...a simple solution:
var obj = {name: 'John', age: null};
var compacted = _.pickBy(obj);
This will only work with lodash 4, pre lodash 4 or underscore.js, use _.pick(obj, _.identity);
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How to set a value of a variable inside a template code?
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If you need to declare a list, use make_list. docs.djangoproject.com/en/1.9/ref/templates/builtins/#make-list
– MrValdez
Jul 1 '16 at 7:55
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