README.md

until loop

    until test-commands; do 
        consequent-commands; 
    done

while loop

    while test-commands; do 
        consequent-commands; 
    done

for loop

    for name [ [in [words …] ] ; ] do 
        commands; 
    done
    
    # or 

    for (( expr1 ; expr2 ; expr3 )) ; do 
        commands ; 
    done