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How to retrieve a module's path?
...e, say you have two files (both of which are on your PYTHONPATH):
#/path1/foo.py
import bar
print(bar.__file__)
and
#/path2/bar.py
import os
print(os.getcwd())
print(__file__)
Running foo.py will give the output:
/path1 # "import bar" causes the line "print(os.getcwd())" to run
/path2/...
Why does a RegExp with global flag give wrong results?
...tart from the last used index, instead of 0. Take a look:
var query = 'Foo B';
var re = new RegExp(query, 'gi');
var result = [];
result.push(re.test('Foo Bar'));
alert(re.lastIndex);
result.push(re.test('Foo Bar'));
If you don't want to manually reset lastIndex to 0 after every test, ju...
Greedy vs. Reluctant vs. Possessive Quantifiers
...n't match the f in the regex, so it backtracks one more step (leaving the "foo" at the end of the string unmatched). Now, the matcher finally matches the f in the regex, and the o and the next o are matched too. Success!
A reluctant or "non-greedy" quantifier first matches as little as possible. So...
What is the difference between JSON and Object Literal Notation?
...ring
a number
an (JSON) object
an array
true
false
null
Duplicate keys ({"foo":"bar","foo":"baz"}) produce undefined, implementation-specific results; the JSON specification specifically does not define their semantics
In JavaScript, object literals can have
String literals, number literals or ...
How to declare string constants in JavaScript? [duplicate]
...m = { //not really an enum, just an object that serves a similar purpose
FOO : "foofoo",
BAR : "barbar",
}
You can now print out 'foofoo' with
jsEnum.FOO
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Using parameters in batch files at Windows command line
...e for a real-life utility.
Let us say that we want to implement a utility foobar. It requires an initial command. It has an optional parameter --foo which takes an optional value (which cannot be another parameter, of course); if the value is missing it defaults to default. It also has an optional ...
jQuery Determine if a matched class has a given id
...rget all elements with a given id, that also have a particular class:
$("#foo.bar"); // Matches <div id="foo" class="bar">
This should look similar to something you'd write in CSS. Note that it won't apply to all #foo elements (though there should only be one), and it won't apply to all .ba...
Is it possible to implement dynamic getters/setters in JavaScript?
...ew Error("This browser doesn't support Proxy");
}
let original = {
"foo": "bar"
};
let proxy = new Proxy(original, {
get(target, name, receiver) {
let rv = Reflect.get(target, name, receiver);
if (typeof rv === "string") {
rv = rv.toUpperCase();
...
Using braces with dynamic variable names in PHP
...he examples below show how the order of evaluation has changed.
Case 1 : $$foo['bar']['baz']
PHP5 interpetation : ${$foo['bar']['baz']}
PHP7 interpetation : ${$foo}['bar']['baz']
Case 2 : $foo->$bar['baz']
PHP5 interpetation : $foo->{$bar['baz']}
PHP7 interpetation : $foo->{$bar}['baz']
...
Get array of object's keys
...
Use Object.keys:
var foo = {
'alpha': 'puffin',
'beta': 'beagle'
};
var keys = Object.keys(foo);
console.log(keys) // ['alpha', 'beta']
// (or maybe some other order, keys are unordered).
This is an ES5 feature. This means it ...