export lookup="a:alfa b:bravo c:charlie d:delta e:echo f:foxtrot g:golf h:hotel i:india j:juliett k:kilo l:lima"

function nato() {
    input=$1
    for C in `echo $input | sed 's/./& /g'`
    do
        # lookup
        for L in $lookup
        do
            k=$(echo $L | cut -d ':' -f 1)
            v=$(echo $L | cut -d ':' -f 2)
            # echo $c $k $v
            if [ "x$k" == "x$C" ]
            then
                echo $v
                continue
            fi
        done
    done | tr '\n' ' '
}

nato glad

echo glad | nato | nato | nato

function nato() {
    input=$1
    echo $input | sed -e 's/a/alpha/g; s/b/bravo/g; s/c/charlie/g; s/d/delta/g; s/e/echo/g; s/f/foxtrot/g; s/g/golf/g; s/h/hotel/g; s/i/india/g; s/j/juliett/g; s/k/kilo/g; s/l/lima/g; s/m/mike/g; s/n/november/g; s/o/oscar/g; s/p/papa/g; s/q/quebec/g; s/r/romeo/g; s/s/sierra/g; s/t/tango/g; s/u/uniform/g; s/v/victor/g; s/w/whiskey/g; s/x/xray/g; s/y/yankee/g; s/z/zulu/g; s/0/zero/g; s/1/one/g; s/2/two/g; s/3/three/g; s/4/four/g; s/5/five/g; s/6/six/g; s/7/seven/g; s/8/eight/g; s/9/nine/g;'
}

nato 'a'

xer () {
    while read -r line; do
        echo ${line}x;
    done
}

echo a | xer | xer | xer

type -a xer

curl -s "https://en.wikipedia.org/wiki/Pipeline_(Unix)" \
  | sed 's/[^a-zA-Z ]/ /g' \
  | tr 'A-Z ' 'a-z\n' \
  | grep '[a-z]' \
  | sort -u \
  | comm -23 - <(sort /usr/share/dict/words) \
  | head -n 20