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How can I check if an argument is defined when starting/calling a batch file?
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The check for whether a commandline argument has been set can be [%1]==[], but, as Dave Costa points out, "%1"=="" will also work.
I also fixed a syntax error in the usage echo to escape the greater-than and less-than signs. In addition, the exit needs...
JavaScript checking for null vs. undefined and difference between == and ===
...hey're falsey:
if (!a) {
// `a` is falsey, which includes `undefined` and `null`
// (and `""`, and `0`, and `NaN`, and [of course] `false`)
}
This is defined by ToBoolean in the spec.
...and what is the difference between the null and undefined?
They're both values usually used to i...
Does Python support short-circuiting?
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Yep, both and and or operators short-circuit -- see the docs.
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Unicode equivalents for \w and \b in Java regular expressions?
Many modern regex implementations interpret the \w character class shorthand as "any letter, digit, or connecting punctuation" (usually: underscore). That way, a regex like \w+ matches words like hello , élève , GOÄ_432 or gefräßig .
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What is the JavaScript >>> operator and how do you use it?
I was looking at code from Mozilla that add a filter method to Array and it had a line of code that confused me.
7 Answers
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Check if two unordered lists are equal [duplicate]
I'm looking for an easy (and quick) way to determine if two unordered lists contain the same elements:
8 Answers
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How can I remove a specific item from an array?
I have an array of numbers and I'm using the .push() method to add elements to it.
97 Answers
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Shell equality operators (=, ==, -eq)
Can someone please explain the difference between = , == and -eq in shell scripting?
4 Answers
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Cutting the videos based on start and end time using ffmpeg
I tried to cut the video using the start and end time of the video by using the following command
9 Answers
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What exactly is a Maven Snapshot and why do we need it?
I am a bit confused about the meaning of a Maven Snapshot and why we build one?
13 Answers
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