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What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
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The first version is preferable:
It works for all kinds of keys, so you can, for example, say {1: 'one', 2: 'two'}. The second variant only works for (some) string keys. Using different kinds of syntax depending on the type of the keys would be an unnecessary inconsisten...
Cost of len() function
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Calling len() on those data types is O(1) in CPython, the most common implementation of the Python language. Here's a link to a table that provides the algorithmic complexity of many different functions in CPython:
TimeComple...
GET URL parameter in PHP
...perglobal: a built-in variable that's populated by PHP and is available in all scopes (you can use it from inside a function without the global keyword).
Since the variable might not exist, you could (and should) ensure your code does not trigger notices with:
<?php
if (isset($_GET['link'])) {
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Read file data without saving it in Flask
...iting my first flask application. I am dealing with file uploads, and basically what I want is to read the data/content of the uploaded file without saving it and then print it on the resulting page. Yes, I am assuming that the user uploads a text file always.
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Standard alternative to GCC's ##__VA_ARGS__ trick?
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It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
How to find out if an installed Eclipse is 32 or 64 bit version?
...e the line with text:
plugins/org.eclipse.equinox.launcher.win32.win32.x86_64_1.0.200.v20090519
then it is 64 bit.
If it would be plugins/org.eclipse.equinox.launcher.win32.win32.x86_32_1.0.200.v20090519 then it is 32 bit.
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How to clear the cache in NetBeans
... me absolutely crazy, trying to track down bugs for hours that weren't actually there -- the class with the main method was not being found, and some custom exception classes were not being recognized as implementing Throwable... I just deleted the stupid cache, and now all of it works fine.
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How do I write data into CSV format as string (not file)?
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I found the answers, all in all, a bit confusing. For Python 2, this usage worked for me:
import csv, io
def csv2string(data):
si = io.BytesIO()
cw = csv.writer(si)
cw.writerow(data)
return si.getvalue().strip('\r\n')
data=[1,2...
Is it possible to implement dynamic getters/setters in JavaScript?
...Here's a simple example that turns any property values that are strings to all caps on retrieval:
"use strict";
if (typeof Proxy == "undefined") {
throw new Error("This browser doesn't support Proxy");
}
let original = {
"foo": "bar"
};
let proxy = new Proxy(original, {
get(...
How to write a JSON file in C#?
...ializeObject(_data.ToArray());
//write string to file
System.IO.File.WriteAllText(@"D:\path.txt", json);
Or the slightly more efficient version of the above code (doesn't use a string as a buffer):
//open file stream
using (StreamWriter file = File.CreateText(@"D:\path.txt"))
{
JsonSerializ...