névtér

A névtér, or namespace, is a container that holds a set of uniquely named identifiers. These identifiers can refer to variables, functions, classes, or other entities within a program or system. The primary purpose of a névtér is to prevent naming conflicts. In large projects or when using multiple libraries, it's common for different parts of the code to use the same name for different things. A névtér resolves this by allowing these identical names to exist as long as they are defined within different névterek.

For example, imagine two different libraries, each defining a function called `print`. Without névterek, if you tried to use both in the same program, it would be ambiguous which `print` function you intended to call. However, if Library A's `print` is in `LibraryA::print` and Library B's `print` is in `LibraryB::print`, you can clearly distinguish between them.

Many programming languages implement névterek. In C++, they are explicitly declared using the `namespace` keyword. In Python, modules themselves act as névterek, meaning that accessing a function `foo` from a module `bar` is done via `bar.foo`. Similarly, Java uses packages to achieve namespacing. Even in operating systems, file paths can be thought of as a hierarchical névtér, where a file named `data.txt` in the `/home/user/documents` directory is distinct from a `data.txt` file in `/var/log`. The concept is fundamental to organizing code and data in a structured and manageable way.