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Why does Python code run faster in a function?
...e names are assigned to indexes. This is possible because you can't dynamically add local variables to a function. Then retrieving a local variable is literally a pointer lookup into the list and a refcount increase on the PyObject which is trivial.
Contrast this to a global lookup (LOAD_GLOBAL), w...
Select all elements with “data-” attribute without using jQuery
Using only JavaScript, what is the most efficient way to select all DOM elements that have a certain data- attribute (let's say data-foo ). The elements may be different tag elements.
...
How do I change the working directory in Python?
...If the exception is thrown, do not perform any recursive operations, especially destructive ones. They will operate on the old path and not the new one.
Return to your old directory when you're done. This can be done in an exception-safe manner by wrapping your chdir call in a context manager, lik...
Executing multi-line statements in the one-line command-line?
...
The issue is not actually with the import statement, it's with anything being before the for loop. Or more specifically, anything appearing before an inlined block.
For example, these all work:
python -c "import sys; print 'rob'"
python -c "imp...
How to obtain the query string from the current URL with JavaScript?
...d turn them into a handy URLSearchParams object.
let paramsString = "name=foo&age=1337"
let searchParams = new URLSearchParams(paramsString);
searchParams.has("name") === true; // true
searchParams.get("age") === "1337"; // true
Notice that the browser support is still limited on this interf...
Relational table naming convention [closed]
...e theory.
Some of the wonderful things about Standards are:
they are all integrated with each other
they work together
they were written by minds greater than ours, so we do not have to
debate them.
The standard table name refers to each row in the table, which is used in the all verbiage, n...
Random “Element is no longer attached to the DOM” StaleElementReferenceException
...r valid. It's close to impossible for WebDriver to make a good guess about all the cases where this might happen - so it throws up its hands and gives control to you, who as the test/app author should know exactly what may or may not happen. What you want to do is explicitly wait until the DOM is in...
Can modules have properties the same way that objects can?
...s? When I put this code in one file x.py and import it from another, then calling x.y results in AttributeError: 'NoneType' object has no attribute 'c', since _M somehow has value None...
– Stephan202
May 19 '09 at 1:35
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Cross compile Go on OSX?
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The env command runs only that call in a custom environment and 'resets' it after it is done. For example run export GOOS=windows, then the command with or without the env and echo $GOOS afterwards. With the env the GOOS was not changed.
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How to convert a byte array to a hex string in Java?
...
From the discussion here, and especially this answer, this is the function I currently use:
private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2...