#!/usr/bin/env bash
# Parameter substitution with defaults and transformations

name=${1:-Guest}
filename=${2:-report.txt}

printf 'Hello, %s\n' "$name"
printf 'File: %s\n' "$filename"
printf 'Uppercase name: %s\n' "${name^^}"
printf 'First three characters: %s\n' "${name:0:3}"
printf 'Character count: %d\n' "${#name}"