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Is it possible to use 'else' in a list comprehension? [duplicate]
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The syntax a if b else c is a ternary operator in Python that evaluates to a if the condition b is true - otherwise, it evaluates to c. It can be used in comprehension statements:
>>> [a if a else 2 for a in [0,1,0,3]]
[2, 1, 2,...
Are “elseif” and “else if” completely synonymous?
Are elseif and else if completely synonymous, or is there a difference?
2 Answers
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How to check if a file exists from inside a batch file [duplicate]
I need to run a utility only if a certain file exists. How do I do this in Windows batch?
3 Answers
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How to check if a file exists in Go?
Go's standard library does not have a function solely intended to check if a file exists or not (like Python's os.path.exists ). What is the idiomatic way to do it?
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Pythonic way to check if a file exists? [duplicate]
Which is the preferred way to check if a file exists and if not create it?
5 Answers
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Check if multiple strings exist in another string
How can I check if any of the strings in an array exists in another string?
15 Answers
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How to detect my browser version and operating system using JavaScript?
...set,ix;
// In Opera, the true version is after "Opera" or after "Version"
if ((verOffset=nAgt.indexOf("Opera"))!=-1) {
browserName = "Opera";
fullVersion = nAgt.substring(verOffset+6);
if ((verOffset=nAgt.indexOf("Version"))!=-1)
fullVersion = nAgt.substring(verOffset+8);
}
// In MSIE, the t...
Javascript: How to check if a string is empty? [duplicate]
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I check length.
if (str.length == 0) {
}
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How to check if the string is empty?
... they are considered false in a Boolean context, so you can just do this:
if not myString:
This is the preferred way if you know that your variable is a string. If your variable could also be some other type then you should use myString == "". See the documentation on Truth Value Testing for ot...
Is “else if” faster than “switch() case”? [duplicate]
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For just a few items, the difference is small. If you have many items you should definitely use a switch.
If a switch contains more than five items, it's implemented using a lookup table or a hash list. This means that all items get the same access ti...