I have seen many programs consisting of structures like the one below typedef struct { int i; char k; } elem; elem user; Why is it needed so often? Any specific reason or applicable area? 15 s 15 As Greg Hewgill said, the typedef means you no longer have to write struct all over the … Read more
In the Go Language Specification, it mentions a brief overview of tags: A field declaration may be followed by an optional string literal tag, which becomes an attribute for all the fields in the corresponding field declaration. The tags are made visible through a reflection interface but are otherwise ignored. // A struct corresponding to … Read more
Following the discussions here on SO I already read several times the remark that mutable structs are “evil” (like in the answer to this question). What’s the actual problem with mutability and structs in C#? 16 s 16 Structs are value types which means they are copied when they are passed around. So if you … Read more
Playing around with Swift, coming from a Java background, why would you want to choose a Struct instead of a Class? Seems like they are the same thing, with a Struct offering less functionality. Why choose it then? 17 s 17 According to the very popular WWDC 2015 talk Protocol Oriented Programming in Swift (video, … Read more
I want to initialize a struct element, split in declaration and initialization. This is what I have: typedef struct MY_TYPE { bool flag; short int value; double stuff; } MY_TYPE; void function(void) { MY_TYPE a; … a = { true, 15, 0.123 } } Is this the way to declare and initialize a local variable … Read more
How can I print (to the console) the Id, Title, Name, etc. of this struct in Golang? type Project struct { Id int64 `json:”project_id”` Title string `json:”title”` Name string `json:”name”` Data Data `json:”data”` Commits Commits `json:”commits”` } 26 s 26 recommended by Go Language
Is there a way to conveniently define a C-like structure in Python? I’m tired of writing stuff like: class MyStruct(): def __init__(self, field1, field2, field3): self.field1 = field1 self.field2 = field2 self.field3 = field3 25 s 25 Update: Data Classes With the introduction of Data Classes in Python 3.7 we get very close. The following … Read more
Why does the sizeof operator return a size larger for a structure than the total sizes of the structure’s members? 12 s 12 This is because of padding added to satisfy alignment constraints. Data structure alignment impacts both performance and correctness of programs: Mis-aligned access might be a hard error (often SIGBUS). Mis-aligned access might … Read more
What’s the difference between struct and class in .NET? 19 s 19 In .NET, there are two categories of types, reference types and value types. Structs are value types and classes are reference types. The general difference is that a reference type lives on the heap, and a value type lives inline, that is, wherever … Read more
In C++, is there any difference between: struct Foo { … }; and: typedef struct { … } Foo; 8 s 8 In C++, there is only a subtle difference. It’s a holdover from C, in which it makes a difference. The C language standard (C89 §3.1.2.3, C99 §6.2.3, and C11 §6.2.3) mandates separate namespaces … Read more
