// Copyright 2018-2025 the Deno authors. MIT license.
// This module is browser compatible.
import { isWindows } from "./_os.ts";
import { extname as posixExtname } from "./posix/extname.ts";
import { extname as windowsExtname } from "./windows/extname.ts";
/**
* Return the extension of the path with leading period (".").
*
* @example Usage
* ```ts
* import { extname } from "@std/path/extname";
* import { assertEquals } from "@std/assert";
*
* if (Deno.build.os === "windows") {
* assertEquals(extname("C:\\home\\user\\Documents\\image.png"), ".png");
* } else {
* assertEquals(extname("/home/user/Documents/image.png"), ".png");
* }
* ```
*
* Note: If you are working with file URLs,
* use the new version of `extname` from `@std/path/unstable-extname`.
*
* @param path Path with extension.
* @returns The file extension. E.g. returns `.ts` for `file.ts`.
*/
export function extname(path: string): string {
return isWindows ? windowsExtname(path) : posixExtname(path);
}
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