var canvas = <HTMLCanvasElement> document.getElementById(“mycanvas”); var ctx = canvas.getContext(“2d”); or using dynamic lookup with the any type (no typechecking): var canvas : any = document.getElementById(“mycanvas”); var ctx = canvas.getContext(“2d”); You can look at the different types in lib.d.ts.
There are 2 types of casting: Implicit casting, when you cast from a type to a wider type, which is done automatically and there is no overhead: String s = “Cast”; Object o = s; // implicit casting Explicit casting, when you go from a wider type to a more narrow one. For this case, … Read more
Static/Dynamic Typing is about when type information is acquired (Either at compile time or at runtime) Strong/Weak Typing is about how strictly types are distinguished (e.g. whether the language tries to do an implicit conversion from strings to numbers). See the wiki-page for more detailed information.
What is the difference between a strongly typed language and a statically typed language? A statically typed language has a type system that is checked at compile time by the implementation (a compiler or interpreter). The type check rejects some programs, and programs that pass the check usually come with some guarantees; for example, the … Read more
Let’s take your example of a Dog and a Cat class, and let’s illustrate using C#: Both a dog and a cat are animals, specifically, quadruped mammals (animals are waaay too general). Let us assume that you have an abstract class Mammal, for both of them: public abstract class Mammal This base class will probably … Read more
Statically typed languages A language is statically typed if the type of a variable is known at compile time. For some languages this means that you as the programmer must specify what type each variable is; other languages (e.g.: Java, C, C++) offer some form of type inference, the capability of the type system to … Read more