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How to check that an object is empty in PHP?
How to find if an object is empty or not in PHP.
11 Answers
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Is there a way to perform “if” in python's lambda
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The syntax you're looking for:
lambda x: True if x % 2 == 0 else False
But you can't use print or raise in a lambda.
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How do I query if a database schema exists
... our build process we run a database update script as we deploy code to 4 different environments. Further, since the same query will get added to until we drop a release into production it has to be able to run multiple times on a given database. Like this:
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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...
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...
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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Array.push() if does not exist?
How can I push into an array if neither values exist? Here is my array:
23 Answers
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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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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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