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Does Javascript pass by reference? [duplicate]
...y value:
function replace(ref) {
ref = {}; // this code does _not_ affect the object passed
}
function update(ref) {
ref.key = 'newvalue'; // this code _does_ affect the _contents_ of the object
}
var a = { key: 'value' };
replace(a); // a still has its original value - it's un...
How do you serialize a model instance in Django?
...ango.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
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python assert with and without parenthesis
...a convenient way to insert debugging assertions into a program:
assert_stmt ::= "assert" expression ["," expression]
The simple form, assert expression, is equivalent to
if __debug__:
if not expression: raise AssertionError
The extended form, assert expression1, expression2, is equi...
How do I convert a Vector of bytes (u8) to a string
...string slice (assuming a UTF-8 encoding):
use std::str;
//
// pub fn from_utf8(v: &[u8]) -> Result<&str, Utf8Error>
//
// Assuming buf: &[u8]
//
fn main() {
let buf = &[0x41u8, 0x41u8, 0x42u8];
let s = match str::from_utf8(buf) {
Ok(v) => v,
E...
Duplicating a MySQL table, indices, and data
...oldtable;
To copy just structure and data use this one:
CREATE TABLE tbl_new AS SELECT * FROM tbl_old;
I've asked this before:
Copy a MySQL table including indexes
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String formatting in Python 3
...format(goals=2, penalties=4)
"({goals} goals, ${penalties})".format(**self.__dict__)
"first goal: {0.goal_list[0]}".format(self)
"second goal: {.goal_list[1]}".format(self)
"conversion rate: {:.2f}".format(self.goals / self.shots) # '0.20'
"conversion rate: {:.2%}".format(self.goals / self.shots) ...
How to read a large file line by line?
...ne from the file.
echo $file->fgets();
}
// Unset the file to call __destruct(), closing the file handle.
$file = null;
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What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
...type. Suppose you want all arrays to have a cool new function called filter_0 that will filter zeroes out.
Array.prototype.filter_0 = function() {
var res = [];
for (var i = 0; i < this.length; i++) {
if (this[i] != 0) {
res.push(this[i]);
}
}
return r...
Random String Generator Returning Same String [duplicate]
...ce of calls to Convert and Floor and NextDouble):
private readonly Random _rng = new Random();
private const string _chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
private string RandomString(int size)
{
char[] buffer = new char[size];
for (int i = 0; i < size; i++)
{
buffer[i] = _c...
How to get function parameter names/values dynamically?
...eturn an array of the parameter names of any function passed in.
var STRIP_COMMENTS = /((\/\/.*$)|(\/\*[\s\S]*?\*\/))/mg;
var ARGUMENT_NAMES = /([^\s,]+)/g;
function getParamNames(func) {
var fnStr = func.toString().replace(STRIP_COMMENTS, '');
var result = fnStr.slice(fnStr.indexOf('(')+1, fnS...