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How can I get the current date and time in UTC or GMT in Java?
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Behrang, according to stackoverflow.com/questions/4123534/…, the MySQL JDBC driver converts a given java.util.Timestamp (or java.util.Date) to the server time zone.
– Derek Mahar
Dec 7 '10 at 21:02
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What is the most efficient way to deep clone an object in JavaScript?
...e(JSON.stringify(object))
const a = {
string: 'string',
number: 123,
bool: false,
nul: null,
date: new Date(), // stringified
undef: undefined, // lost
inf: Infinity, // forced to 'null'
re: /.*/, // lost
}
console.log(a);
console.log(typeof a.date); // Date obje...
Pass a data.frame column name to a function
...e more about tidyeval here.
library(rlang)
library(tidyverse)
set.seed(123)
df <- data.frame(B = rnorm(10), D = rnorm(10))
Use column names as strings
fun3 <- function(x, ...) {
# capture strings and create variables
dots <- ensyms(...)
# unquote to evaluate inside dplyr verbs
...
What are the differences between a pointer variable and a reference variable in C++?
...e of that object becomes the lifetime of the reference.
std::string s1 = "123";
std::string s2 = "456";
std::string s3_copy = s1 + s2;
const std::string& s3_reference = s1 + s2;
In this example s3_copy copies the temporary object that is a result of the concatenation. Whereas s3_reference in...
Understanding the map function
...s, but the map returns a map object - for example I get this: <map at 0x123a49978> Which I then must coerce into a list.
– leerssej
Dec 3 '19 at 6:18
add a comment
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What is Type-safe?
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On the down side, with type safe languages, when you have a string like "123" and you want to operate on it like an int, you have to write more code to convert the string to an int, or when you have an
RESTful Alternatives to DELETE Request Body
...ngs. The query string is part of the URI. Sending a DELETE request to /foo?123 means you are deleting a different resource than if you were to send DELETE to /foo?456.
– Nicholas Shanks
Jan 25 '16 at 17:38
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Check synchronously if file/directory exists in Node.js
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123
Looking at the source, there's a synchronous version of path.exists - path.existsSync. Looks ...
What requirement was the tuple designed to solve?
...e/use a tuple in a very efficient and simple way:
var person = (Id:"123", Name:"john"); //create tuble with two items
Console.WriteLine($"{person.Id} name:{person.Name}") //access its fields
Returning more than one value from a method:
public (double sum, double average) ComputeSu...
Git log to get commits only for a specific branch
...en there is no default & no pattern
| | defined.
| |
| * commit 80c123b9dbd1c1b3301ec1270adc6c07824aeb5c
| | Author: Mark Story <mark@mark-story.com>
| | Date: Sun Aug 28 22:35:20 2016 -0400
| |
| | Do fewer allocations for simple default values.
| |
| | Don't allocate arrays...