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How can I check if an element exists in the visible DOM?
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It seems some people are landing here, and simply want to know if an element exists (a little bit different to the original question).
That's as simple as using any of the browser's selecting method, and checking it for a truthy value (generally).
For example, if my element had an id o...
How to write file if parent folder doesn't exist?
...File(path, contents, cb) {
mkdirp(getDirName(path), function (err) {
if (err) return cb(err);
fs.writeFile(path, contents, cb);
});
}
If the whole path already exists, mkdirp is a noop. Otherwise it creates all missing directories for you.
This module does what you want: https://npm...
How to check if a list is empty in Python? [duplicate]
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if not myList:
print "Nothing here"
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How to check if a query string value is present via JavaScript?
How can I check if the query string contains a q= in it using JavaScript or jQuery?
10 Answers
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Clone Object without reference javascript [duplicate]
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If you use an = statement to assign a value to a var with an object on the right side, javascript will not copy but reference the object.
You can use lodash's clone method
var obj = {a: 25, b: 50, c: 75};
var A = _.clone(ob...
Array.push() if does not exist?
How can I push into an array if neither values exist? Here is my array:
23 Answers
23
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What’s the best way to check if a file exists in C++? (cross platform)
I have read the answers for What's the best way to check if a file exists in C? (cross platform) , but I'm wondering if there is a better way to do this using standard c++ libs? Preferably without trying to open the file at all.
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Check if Python Package is installed
What's a good way to check if a package is installed while within a Python script? I know it's easy from the interpreter, but I need to do it within a script.
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How to check if a python module exists without importing it
I need to know if a python module exists, without importing it.
13 Answers
13
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What is the pythonic way to detect the last element in a 'for' loop?
...ial case instead of the last one:
first = True
for data in data_list:
if first:
first = False
else:
between_items()
item()
This will work for any iterable, even for those that have no len():
file = open('/path/to/file')
for line in file:
process_line(line)
#...