bash: using test and or ([ ] and -o)

[lux11]

RE: Beginning scripting

Hello:
Here's an easy one to start the New Year with.

What is a more efficient way to construct the tests below?

#!/bin/bash
echo -n "Guess three colors. Enter all in lowercase.
"
read word1
read word2
read word3

#TEST 1
color=red
[ "$color" = "$word1" -o "$color" = "$word2" -o "$color" = "$word3" ]
A=$?

#TEST 2
color=white
[ "$color" = "$word1" -o "$color" = "$word2" -o "$color" = "$word3" ]
B=$?

#TEST 3
color=blue
[ "$color" = "$word1" -o "$color" = "$word2" -o "$color" = "$word3" ]
C=$?

D=$((A+B+C))

if [ $D = 0 ]; then
echo "Congratulations! You guessed all three correctly."
else
echo "Sorry, try again."
fi

Thanks,
Lux

[atreyu]

try this - it uses loops and arrays:

#!/bin/bash
echo -n "Guess three colors. Enter all in lowercase.
"
read word1
read word2
read word3

# array to hold colors guessed correctly
declare -a guessed

# loop thru all guessed words 
for word in $word1 $word2 $word3; do 

  # loop thru the list of correct colors
  for color in red white blue; do
    if [ "$word" == "$color" ]; then
      guessed[${#guessed[*]}]=$color
      break
    fi
  done
done

# if there are 3 entries in the array, they must have guessed them all
if [ ${#guessed[*]} -eq 3 ]; then
  echo "Congratulations! You guessed all three correctly."
else
  echo "Sorry, try again."
fi

this way makes it easy to add more colors/inputs, too.

[lux11]

Thank you for the alternate script, atreyu, and for the accompanying explanations. I do like your solution much better than the one I proposed and agree that it lends itself to easier expansion. However, I would still like to know if there is simpler way to write the test expression. Specifically, I'm wondering if there is a way to change this

#TEST 2
color=white
[ "$color" = "$word1" -o "$color" = "$word2" -o "$color" = "$word3" ]
B=$?

to something more like this

#TEST 2
color=white
[ "$color" = ("$word1" -o "$word2" -o "$word3") ]
B=$?

which of course does not work as shown.
Thanks for the help.
Lux

[atreyu]

oh, now i see your question. i don't know how to do what you are suggesting in bash, but it did make me think of another way -using bash's case statement, e.g.:

declare -i ok
ok=0
case word1 in
  red) ok+=1 ;;
  blue) ok+=1 ;;
  green) ok+=1 ;;
esac
echo "You guessed $ok correct colors"