Namespace vs module
- TypeScript course
- Intermediate
- Lesson 56/89
- 4 min
Learn the difference between namespace and module.
Namespace vs module
A namespace groups related code under a name in the global scope. A module is file-based; each file has its own scope and connects via import/export. Modules are recommended for new projects; namespaces are an older pattern.
// namespace pattern (legacy)
namespace Hesap {
export function topla(a, b) { return a + b; }
}
// module pattern (modern)
// file: hesap.ts
export function topla(a, b) { return a + b; }When to use a namespace?
Namespaces are still useful when porting legacy JavaScript libraries to TypeScript or for single-file utilities. But for a modern project spanning multiple files, modules are more appropriate; they provide per-file independent scope and explicit dependency declarations.
Practice Legacy-pattern library header
Using the object pattern that is the compiled equivalent of a namespace structure, define an object named Kutuphane. It should have methods ekle(): string and sil(): string; ekle returns "eklendi", sil returns "silindi". Call them from outside as Kutuphane.ekle and Kutuphane.sil, printing the results on separate lines.
Starter code
// Kutuphane adında bir nesne tanımla
// ekle metodunu ekle, "eklendi" döndürsün
// sil metodunu ekle, "silindi" döndürsün
// her ikisini de çağır, sonuçları ayrı satırda yazdırSample solution
const Kutuphane = {
ekle(): string {
return "eklendi";
},
sil(): string {
return "silindi";
}
};
console.log(Kutuphane.ekle());
console.log(Kutuphane.sil());Expected output
eklendi silindi
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What is the recommended code organization for a new TypeScript project?
- A single large namespace in one file
- File-based module usage Correct answer
- Only global variables
- No organization at all
Explanation: For new projects, file-based module usage is recommended. Namespaces are a legacy pattern; global variables and no organization are bad practice.
2 Declare a namespace
____ Hesap {
export function topla(a: number, b: number): number {
return a + b;
}
}namespace Hesap {
export function topla(a: number, b: number): number {
return a + b;
}
}Explanation: To group in the global scope you use the namespace keyword. module is file-based; package and scope are not keywords for declaring a namespace in TypeScript.
3 Namespace and module comparison
| Term | Meaning |
|---|---|
namespace Ad { } |
Global scope grouping |
import { } from "./mod" |
File-based import |
Ad.üye |
Namespace member access |
her dosya kendi kapsamında |
Module encapsulation rule |