This is a simplified version of the original problem. I have a class called Person: public class Person { public string Name { get; set; } public int Age { get; set; } public int Weight { get; set; } public DateTime FavouriteDay { get; set; } } …and lets say an instance: var bob … Read more
This is just a curiosity question I was wondering if anyone had a good answer to: In the .NET Framework Class Library we have for example these two methods: public static IQueryable<TSource> Where<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, bool>> predicate ) public static IEnumerable<TSource> Where<TSource>( this IEnumerable<TSource> source, Func<TSource, bool> predicate ) Why do they use … Read more
I want an idiomatic way to find the first element in a list that matches a predicate. The current code is quite ugly: [x for x in seq if predicate(x)][0] I’ve thought about changing it to: from itertools import dropwhile dropwhile(lambda x: not predicate(x), seq).next() But there must be something more elegant… And it would … Read more
Can you explain to me: What is a Predicate Delegate? Where should we use predicates? Any best practices when using predicates? Descriptive source code will be appreciated. 10 Answers 10
In Java 8, you can use a method reference to filter a stream, for example: Stream<String> s = …; long emptyStrings = s.filter(String::isEmpty).count(); Is there a way to create a method reference that is the negation of an existing one, i.e. something like: long nonEmptyStrings = s.filter(not(String::isEmpty)).count(); I could create the not method like below … Read more
