Hello,
The example on parameter expansion[1] should perhaps read : $ echo ${v:-unset} instead of : $ echo ${v-unset} Yes ? More context: ---8<--- ${parameter:-word} If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of parameter is substituted. $ v=123 $ echo ${v-unset} 123 --->8--- Thanks ! -- 1. https://www.gnu.org/software/bash/manual/html_node/Shell-Parameter-Expansion.html