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How do I check if a string is a number (float)?
What is the best possible way to check if a string can be represented as a number in Python?
33 Answers
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What are the best practices for using a GUID as a primary key, specifically regarding performance?
I have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, b...
How can I make a weak protocol reference in 'pure' Swift (without @objc)
weak references don't seem to work in Swift unless a protocol is declared as @objc , which I don't want in a pure Swift app.
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What's the scope of the “using” declaration in C++?
I'm using the 'using' declaration in C++ to add std::string and std::vector to the local namespace (to save typing unnecessary 'std::'s).
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How to check if a char is equal to an empty space?
Here's what I've got:
11 Answers
11
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Functional, Declarative, and Imperative Programming [closed]
What do the terms functional, declarative, and imperative programming mean?
14 Answers
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Why is there “data” and “newtype” in Haskell? [duplicate]
It seems that a newtype definition is just a data definition that obeys some restrictions (e.g., only one constructor), and that due to these restrictions the runtime system can handle newtype s more efficiently. And the handling of pattern matching for undefined values is slightly different.
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Is it safe to get values from a java.util.HashMap from multiple threads (no modification)?
There is a case where a map will be constructed, and once it is initialized, it will never be modified again. It will however, be accessed (via get(key) only) from multiple threads. Is it safe to use a java.util.HashMap in this way?
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How many files can I put in a directory?
Does it matter how many files I keep in a single directory? If so, how many files in a directory is too many, and what are the impacts of having too many files? (This is on a Linux server.)
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Is a URL allowed to contain a space?
Is a URI (specifically an HTTP URL) allowed to contain one or more space characters? If a URL must be encoded, is + just a commonly followed convention, or a legitimate alternative?
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