In C++11, no – there’s no penalty. I would even consider it a very good style to not pollute any “more visible” scopes with you implementation details, unless, of course, you want to reuse that functor elsewhere. However, lambdas are essentially a condensed form of this idea, and should usually be preferred if you are … Read more
Currently there’s no compile-time optimisation; the values are padded to 8 bytes on x64. You can manually arrange structs to optimally utilise space; typically by going from larger types to smaller; 8 consecutive byte fields for example, will only use 8 bytes, but a single byte would be padded to an 8 byte alignment, consider … Read more
The Vector3.Normalize() method has a pointer receiver, so in order to call this method, a pointer to Vector3 value is required (*Vector3). In your first example you store the return value of Vector3.Minus() in a variable, which will be of type Vector3. Variables in Go are addressable, and when you write diff.Normalize(), this is a … Read more
struct is a keyword in Go. It is used to define struct types, which is a sequence of named elements. For example: type Person struct { Name string Age int } The struct{} is a struct type with zero elements. It is often used when no information is to be stored. It has the benefit … Read more
The approach you’ve outlined is roughly correct, although you should use offsetof instead of attempting to figure out the offset on your own. I’m not sure why you mention memset — it sets the contents of a block to a specified value, which seems quite unrelated to the question at hand. Here’s some code to … Read more
-> is a shorthand for (*x).field, where x is a pointer to a variable of type struct account, and field is a field in the struct, such as account_number. If you have a pointer to a struct, then saying accountp->account_number; is much more concise than (*accountp).account_number;
is there a way to do it without extracting their “inner” values every time with pattern matching, and without implementing the Add, Sub, … traits and overloading operators? No, the only way is to implement the traits manually. Rust doesn’t have an equivalent to the Haskell’s GHC extension GeneralizedNewtypeDeriving which allows deriving on wrapper types … Read more
It’s good practice to keep the mutex close to the data it is destined to protect. If a mutex ought to protect concurrent access to fields of a struct value, it’s very convenient to add the mutex as a field of that struct, so its purpose is obvious. If in your app there is only … Read more
Swift 4.1 (and above) Updated answer: Starting from Swift 4.1, all you have to is to conform to the Equatable protocol without the need of implementing the == method. See: SE-0185 – Synthesizing Equatable and Hashable conformance. Example: struct MyStruct: Equatable { var id: Int var value: String } let obj1 = MyStruct(id: 101, value: … Read more
Before we start: Let me point out that a lot of the confusion around this syntax comes because in both C and C++ you can use the = {0} syntax to initialize all members of a C-style array to zero! See here: https://en.cppreference.com/w/c/language/array_initialization. So, this works: // z has type int[3] and holds all zeroes, … Read more