Python method-wrapper type?

It appears that the type <method-wrapper ..> is used by CPython for methods implemented in C code. Basically the type doesn’t wrap another method. Instead it wraps a C-implemented function as an bound method. In this way <method-wrapper> is exactly like a <bound-method> except that it is implemented in C. In CPython there are two … Read more

How to create a circularly referenced type in TypeScript?

The creator of TypeScript explains how to create recursive types here. The workaround for the circular reference is to use extends Array. In your case this would lead to this solution: type Document = number | string | DocumentArray; interface DocumentArray extends Array<Document> { } Update (TypeScript 3.7) Starting with TypeScript 3.7, recursive type aliases … Read more

JAXB: How to change XJC-generated classes names when attr type is specified in XSD?

JAXB provides two ways to accomplish this: 1. Inline Schema Anntotations You can use JAXB schema annotations to control the class names. <xs:schema xmlns:xs=”http://www.w3.org/2001/XMLSchema” xmlns:jaxb=”http://java.sun.com/xml/ns/jaxb” jaxb:version=”2.1″> <xs:complexType name=”itemType”> <xs:annotation> <xs:appinfo> <jaxb:class name=”Item”/> </xs:appinfo> </xs:annotation> <xs:attribute name=”id” type=”xs:string” use=”required”/> </xs:complexType> </xs:schema> 2. External Binding File This customization can also be done via and external binding file: … Read more

How do I print in Rust the type of a variable?

You can use the std::any::type_name function. This doesn’t need a nightly compiler or an external crate, and the results are quite correct: fn print_type_of<T>(_: &T) { println!(“{}”, std::any::type_name::<T>()) } fn main() { let s = “Hello”; let i = 42; print_type_of(&s); // &str print_type_of(&i); // i32 print_type_of(&main); // playground::main print_type_of(&print_type_of::<i32>); // playground::print_type_of<i32> print_type_of(&{ || “Hi!” … Read more

Why can’t Rust infer the resulting type of Iterator::sum?

The way sum is defined, the return value is open-ended; more than one type can implement the trait Sum<i32>. Here’s an example where different types for a are used, both of which compile: #[derive(Clone, Copy)] struct Summer { s: isize, } impl Summer { fn pow(&self, p: isize) { println!(“pow({})”, p); } } impl std::iter::Sum<i32> … Read more