Compare "pure" Bash vs call to `tr`

sarc.sh

#!/usr/bin/env bash

foo() {
  local value="The Quick Brown FOX umped over The Lazy Dog."

  local -i loopCount=1000
  local -i i=0
  for (( i = 0; i < loopCount; ++i )); do
    local newVal=""
    newVal="${value,,}"
    printf "%s\n" "$newVal"
  done
}


bar() {
  local value="The Quick Brown FOX umped over The Lazy Dog."

  local -i loopCount=1000
  local -i i=0
  for (( i = 0; i < loopCount; ++i )); do
    # shellcheck disable=SC2155
    local newVal=$(echo "$value" | tr '[:upper:]' '[:lower:]')
    printf "%s\n" "$newVal"
  done
}

baz() {
  local value="$*"

  printf "%s\n" "${value,,}"
}