An immutable type that may contain a value or reference.
I want to prepend a stream with an Optional. Since Stream.concat can only concatinate Streams I have this question: …
java java-8 java-stream optionalI'm creating an NSManagedObject subclass in Swift and I get an error when I make an Optional property that's of …
objective-c swift nsmanagedobject optionalI have a class called Address which looks like this: @Value class Address { @NotNull String userId; @NotNull String line1; String …
java optional lombokI'm a little confused around flatMap (added to Swift 1.2) Say I have an array of some optional type e.g. …
swift functional-programming optional higher-order-functions flatmapI have a simple Person class in Swift that looks about like this: class Person { var name = "John Doe" var …
arrays swift optionalI've been playing around with Swift and discovered that when down casting an object to be inserted into a dictionary, …
swift optional downcast forced-unwrappingIn javascript, Optional Chaining Operator is supported by the babel plugin. But I can't find how to do this in …
javascript typescript optional chainingIn Swift I can declare a constant of type Any and put a String into it. let any: Any = "hello …
swift optionalWhy std::optional (std::experimental::optional in libc++ at the moment) does not have specialization for reference types (compared with …
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