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How to convert std::string to lower case?

...thm/string.hpp> std::string str = "HELLO, WORLD!"; boost::algorithm::to_lower(str); // modifies str Or, for non-in-place: #include <boost/algorithm/string.hpp> const std::string str = "HELLO, WORLD!"; const std::string lower_str = boost::algorithm::to_lower_copy(str); ...
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How to check for valid email address? [duplicate]

... to check, it might be faster to compile the regex first: import re EMAIL_REGEX = re.compile(r"... regex here ...") if not EMAIL_REGEX.match(email): # whatever Another option is to use the validate_email package, which actually contacts the SMTP server to verify that the address exists. Thi...
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Embedding SVG into ReactJS

...rHTML: render: function() { return <span dangerouslySetInnerHTML={{__html: "<svg>...</svg>"}} />; } and React will include the markup directly without processing it at all. share | ...
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What is Weak Head Normal Form?

...es for an expression to be in WHNF: A constructor: constructor expression_1 expression_2 ... A built-in function with too few arguments, like (+) 2 or sqrt A lambda-expression: \x -> expression In other words, the head of the expression (i.e. the outermost function application) cannot be eval...
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Why is a ConcurrentModificationException thrown and how to debug it

...ator is still designed for single-thread access). – G__ May 9 '11 at 20:51 This solution has no point, because Maps do...
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How to compare 2 files fast using .NET?

...re the resulting numbers. Here's what I came up with: const int BYTES_TO_READ = sizeof(Int64); static bool FilesAreEqual(FileInfo first, FileInfo second) { if (first.Length != second.Length) return false; if (string.Equals(first.FullName, second.FullName, ...
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SqlException from Entity Framework - New transaction is not allowed because there are other threads

... the IList<T>. Example: IList<Client> clientList = from a in _dbFeed.Client.Include("Auto") select a; foreach (RivWorks.Model.NegotiationAutos.Client client in clientList) { var companyFeedDetailList = from a in _dbRiv.AutoNegotiationDetails where a.ClientID == client.ClientID selec...
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Why doesn't Haskell's Prelude.read return a Maybe?

...ybe s = case reads s of [(x, "")] -> Just x _ -> Nothing share | improve this answer | follow | ...
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Mean per group in a data.frame [duplicate]

... object. It’s easier to do what you’re after with dplyr: d %>% group_by(Name) %>% mutate(mean1=mean(Rate1), mean2=mean(Rate2)) – jbaums May 29 '19 at 9:48 ...
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How are people managing authentication in Go? [closed]

...-nuts mailing list: https://groups.google.com/forum/#!msg/golang-nuts/GE7a_5C5kbA/fdSnH41pOPYJ This provides a suggested schema and server-side implementation as a basis for custom authentication. The client-side code is still up to you. (I hope the author of the post sees this: Thanks!) Excerpt...