import { type IEnvVarValueHandler } from "https://deno.land/x/cliffy@v0.20.1/command/mod.ts";
definition: (val: T) => unknown
x/cliffy/command/mod.ts>IEnvVarValueHandler
import { type IEnvVarValueHandler } from "https://deno.land/x/cliffy@v0.20.1/command/mod.ts";