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Can I have an IF block in DOS batch file?
...1 line if statement body? I think I found somewhere that I could use () for an if block just like the {} used in C-like programming languages, but it is not executing the statements when I try this. No error message either. This my code:
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What really is a deque in STL?
...nds in constant time, but I am troubled by the promise made by the operator [] to be done in constant time. In a linked list, arbitrary access should be O(n), right?
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What is a Lambda?
...ld someone provide a good description of what a Lambda is? We have a tag for them and they're on the secrets of C# question, but I have yet to find a good definition and explanation of what they are in the first place.
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What is the right way to check for a null string in Objective-C?
...since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title == (id)[NSNull null] || title.length == 0 ) title = @"Something";
Note how you can use the fact that even if title is nil, title.le...
How to extract URL parameters from a URL with Ruby or Rails?
...to turn any given URL string into a HASH?
You can try http://www.ruby-doc.org/stdlib/libdoc/cgi/rdoc/classes/CGI.html#M000075
require 'cgi'
CGI::parse('param1=value1&param2=value2&param3=value3')
returns
{"param1"=>["value1"], "param2"=>["value2"], "param3"=>["value3"]}
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How to avoid 'cannot read property of undefined' errors?
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Update:
If you use JavaScript according to ECMAScript 2020 or later, see optional chaining.
TypeScript has added support for optional chaining in version 3.7.
// use it like this
obj?.a?.lot?.of?.properties
Solution for JavaScript before ECMASCript 202...
The maximum value for an int type in Go
How does one specify the maximum value representable for an unsigned integer type?
10 Answers
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How do I get the number of days between two dates in JavaScript?
How do I get the number of days between two dates in JavaScript? For example, given two dates in input boxes:
37 Answers
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Return a value from AsyncTask in Android [duplicate]
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It not work, e.g. myTask mTask = new myTask(); mTask.execute(); will not return the myHandledValueType.
– Cheung
Aug 30 '13 at 5:19
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How do I fix "The expression of type List needs unchecked conversion…'?
...>, then cast each element of the sf.getEntries() result to SyndEntry before adding it to your new list. Collections.checkedList does not do this checking for you—although it would have been possible to implement it to do so.
By doing your own cast up front, you're "complying with the warranty...