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need help simplifying an if statement

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# 1  
Old 11-02-2011
need help simplifying an if statement
the code below is a small fragment of the actual line, in fact i have about 20 values i'm comparing and want to know if it can be simplified. other than the x.xx.xx format of the value they have nothing in common

Code:
if [ "$ver" = "4.02.011" ] || [ "$ver" = "4.04.013" ] || [ "$ver" = "4.06.011" || [ "$ver" = "5.02.010" ]; then
do this
else
do this
fi

any suggestions?
# 2  
Old 11-02-2011
Code:
#!/bin/ksh

valid='4.02.011|4.04.013|4.06.011|5.02.010'

eval "case \$ver in $valid) echo 'do this' ;;
                    *) echo 'do that' ;;
      esac"

This User Gave Thanks to vgersh99 For This Post:
crimso
# 3  
Old 11-02-2011
Write all of the values into a file, call it test.dat
Code:
grep -q "$ver" test.dat
if [ $? - eq 0 ];  then
   do_this  # true, found in file
else
   do_that  # not in file
fi

# 4  
Old 11-02-2011
Slight modification to that:

Code:
if grep -q "^$ver\$" filename
then
        echo "Matches"
else
        echo "Doesn't match"
fi

This will prevent partial matches from happening, it will match only whole lines.

Unfortunately . is a special character to grep, so it's possible 4.02.011 could still match against 4302911.
# 5  
Old 11-02-2011
grep -F (on modern systems that support it) gets around the need for that.
Not all systems support grep -F. -F == fixed strings, no regular expressions

It is POSIX behavior.

grep
# 6  
Old 11-02-2011
Quote:
Originally Posted by jim mcnamara
grep -F (on modern systems that support it) gets around the need for that.
Not all systems support grep -F. -F == fixed strings, no regular expressions

It is POSIX behavior.

grep
or one can use 'fgrep' to search for 'literal strings'.
# 7  
Old 11-02-2011
appreciate all the feedback as knowing more than one way to handle it is always good. the first post is the most efficient for our means as maintaining a file outside of this script would not get approved. thanx all for chiming in!
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