method CliffyCommand.prototype.hasEnvVarimport { CliffyCommand } from "https://dotland.deno.dev/x/nessie@2.0.11/deps.ts"; hasEnvVar(name: string, hidden?: boolean): booleanChecks whether the command has an environment variable with given name or not. Parametersname: stringName of the environment variable. optionalhidden: booleanInclude hidden environment variable. Returnsboolean