Print values of an array while stripping out some parts of the string

Question

Is there a more efficient way to run this? I am especially interested in a way which perhaps does not require a for loop...

shopt -s nullglob
file=
declare -a ARRAY1
ARRAY1=( ~lettus_*.sh )
for file in ${ARRAY1[@]}
do
 ##
 ## Get <name> from /some/path/lettus_name.sh
 ##
 # remove .sh extension
 file=${file%.sh}
 # remove full path up to and including lettus_
 file=${file//*lettus_}
 echo $file
done
shopt -u nullglob

Answer 1

1. I'm assuming that file=${file//*lettus_} is supposed to be file=${file##*lettus_}.

2. Don't do file=. There is no reason to declare the file variable before-hand. Using it is a the loop variable automatically creates it.

3. Get rid of the temporary ARRAY1 variable (which fyi is not a good variable name). Just do for file in lettus_*.sh. In fact, since you don't quote ${ARRAY1[@]}, word-splitting would make your program fail in some cases.

4. Why do you want a more efficient way? This should run in a split-second unless you have a million files.

• Felipe Alvarez: Yes. Need to change to file=${file##*lettus_}. Thanks. And you are right, it will be very fast. I just thought I was perhaps scripting this naively.....
• gardenhead: Well "naively" doesn't just have to do with performance. All programming -- even "simple" shell scripting -- is a trade-off among many competing factors, two of which are speed and code clarity. In most cases, clarity wins out :)