To save piles of typing when debugging bash scripts, a dump() function that understands both regular and associative arrays:

is_array() {
    if [ -n "$BASH" ]; then
        declare -p ${1} 2> /dev/null | grep 'declare \-a' >/dev/null && return 0
    fi
    return 1
}

is_hash() {
    if [ -n "$BASH" ]; then
        declare -p ${1} 2> /dev/null | grep 'declare \-A' >/dev/null && return 0
    fi
    return 1
}

dump() {
    for var; do
        if is_array ${var} ; then
            echo ${var} = $(eval "echo \${${var}[@]}")
        elif is_hash ${var} ; then
            dump_hash ${var}
        else
            echo ${var} = $(eval "echo \$${var}")
        fi
    done
}

dump_hash() {
    h=${1}
    for k in $(eval "echo \${!${h}[@]}"); do
        echo "$h[${k}]" = $(eval "echo \${${h}[${k}]}")
    done
}

First, it can dump regular variables:

$ dump HOME HISTFILE HISTSIZE
HOME = /home/rpjday
HISTFILE = /home/rpjday/.bash_history
HISTSIZE = 1000
$

Next, dumping regular arrays:

$ people=(fred barney wilma betty)
$ dump people
people = fred barney wilma betty
$

Finally, dump a bash associative array:

$ declare -A wife
$ wife[fred]=wilma
$ wife[barney]=betty
$ dump wife
wife[fred] = wilma
wife[barney] = betty
$