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Deno.Env - Deno documentation
interface Deno.Env
allow-env
An interface containing methods to interact with the process environment variables.

Methods

get(key: string): string | undefined
Retrieve the value of an environment variable. Returns `undefined` if the supplied environment variable is not defined. ```ts console.log(Deno.env.get("HOME")); // e.g. outputs "/home/alice" console.log(Deno.env.get("MADE_UP_VAR")); // outputs "undefined" ``` Requires `allow-env` permission.
set(
key: string,
value: string,
): void
Set the value of an environment variable. ```ts Deno.env.set("SOME_VAR", "Value"); Deno.env.get("SOME_VAR"); // outputs "Value" ``` Requires `allow-env` permission.
delete(key: string): void
Delete the value of an environment variable. ```ts Deno.env.set("SOME_VAR", "Value"); Deno.env.delete("SOME_VAR"); // outputs "undefined" ``` Requires `allow-env` permission.
has(key: string): boolean
Check whether an environment variable is present or not. ```ts Deno.env.set("SOME_VAR", "Value"); Deno.env.has("SOME_VAR"); // outputs true ``` Requires `allow-env` permission.
toObject(): { [index: string]: string; }
Returns a snapshot of the environment variables at invocation as a simple object of keys and values. ```ts Deno.env.set("TEST_VAR", "A"); const myEnv = Deno.env.toObject(); console.log(myEnv.SHELL); Deno.env.set("TEST_VAR", "B"); console.log(myEnv.TEST_VAR); // outputs "A" ``` Requires `allow-env` permission.