itarticle generic variance in scala: 泛型变化 in scala LSP (Liskov substitution principle) subtype,(co-,contra-,in)Variance Function[-P,+R] 0
itarticle SOLID IntroductionSingle responsibility principleOpen–closed principleLiskov substitution principleInterface segregation principleDependency inversion principle Single responsibility principle Open–closed principle Liskov substitution principle Interface segregation principle Dependency inversion principle 0