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Difference between fmt.Println() and println() in Go
...
println is an built-in function (into the runtime) which may eventually be removed, while the fmt package is in the standard library, which will persist. See the spec on that topic.
For language developers it is handy to have a println without dependencies, but the way to go is to use the f...
How to import data from mongodb to pandas?
...odes I'm using:
import pandas as pd
from pymongo import MongoClient
def _connect_mongo(host, port, username, password, db):
""" A util for making a connection to mongo """
if username and password:
mongo_uri = 'mongodb://%s:%s@%s:%s/%s' % (username, password, host, port, db)
...
Can you supply arguments to the map(&:method) syntax in Ruby?
... the shorthand block:
[['0', '1'], ['2', '3']].map(&:map.with(&:to_i))
# => [[0, 1], [2, 3]]
[%w(a b), %w(c d)].map(&:inject.with(&:+))
# => ["ab", "cd"]
[(1..5), (6..10)].map(&:map.with(&:*.with(2)))
# => [[2, 4, 6, 8, 10], [12, 14, 16, 18, 20]]
Here is a conve...
Execute a terminal command from a Cocoa app
...;
NSFileHandle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;
[task launch];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
NSString *grepOutput = [[NSS...
What does the “===” operator do in Ruby? [duplicate]
...
Just like with every other method in Ruby (or actually pretty much any object-oriented language),
a === b
means whatever the author of a's class wants it to mean.
However, if you don't want to confuse the heck out of your colleagues, the convention is that === is the cas...
How to automatically convert strongly typed enum into int?
The a::LOCAL_A is what the strongly typed enum is trying to achieve, but there is a small difference : normal enums can be converted into integer type, while strongly typed enums can not do it without a cast.
...
Pass Method as Parameter using C#
I have several methods all with the same parameter types and return values but different names and blocks. I want to pass the name of the method to run to another method that will invoke the passed method.
...
How does inheritance work for Attributes?
...AttributeUsage (Inherited = True)]
MyUberAttribute : Attribute
{
string _SpecialName;
public string SpecialName
{
get { return _SpecialName; }
set { _SpecialName = value; }
}
}
Then use the Attribute by decorating a super-class...
[MyUberAttribute(SpecialName = "Bob")]
clas...
How to unset a JavaScript variable?
I have a global variable in JavaScript (actually a window property, but I don't think it matters) which was already populated by a previous script but I don't want another script that will run later to see its value or that it was even defined.
...
How to format a java.sql Timestamp for displaying?
...SQL and want the database itself to perform the conversion, use this:
DATE_FORMAT(date,format)
If you prefer to format using Java, use this:
java.text.SimpleDateFormat
SimpleDateFormat dateFormat = new SimpleDateFormat("M/dd/yyyy");
dateFormat.format( new Date() );
...