两个bash数组中的模式匹配

Question

I found quite a few posts on this but couldn't put together the pieces to solve my issue. So say I have two arrays:

array1=( adir bdir anicedir )
array2=( adir anice )

I would like to have a third array like so

array3=( adir anicedir )

More specifically if the first 5 characters of the i-th element in array2 match the first 5 characters of any element in array1 then substitute array2[i] with array1[i]

Answer 1

There's nothing particularly short, because bash isn't a data-processing language. You need to use a loop.

array1=( adir bdir anicedir )
array2=( adir anice )
array3=()

for val2 in "${array2[@]}"; do
    for val1 in "${array1[@]}"; do
        if [[ ${val1:0:5} == "${val2:0:5}" ]]; then
            array3+=("$val1")
            break
        fi
    done
done

Quoting the right-hand side of == ensures that literal string comparison, not pattern matching, is performed.