Find Item in Array / Replace With Array Using Awk?

Return to another shared global variable:

find_replace_in_list() {
    local -n _list=$1 _replace_list=$3
    __A0=()

    for i in "${!_list[@]}"; do
        if [[ ${_list[i]} == "$2" ]]; then
            __A0+=("${_replace_list[@]}" "${_list[@]:i + 1}")
            break
        fi

        __A0[i]=${_list[i]}
    done
}

Modify original list:

find_replace_in_list() {
    local -n _list=$1 _replace_list=$3
    local counter=0

    for i in "${!_list[@]}"; do
        if [[ ${_list[i]} == "$2" ]]; then
            _list=("${_list[@]:0:counter}" "${_replace_list[@]}" "${_list[@]:i + 1}")
            break
        fi

        (( ++counter ))
    done
}

You can use nameref's (declare -n) to pass data to/from the function.

Also, instead of trying to reindex a current array we'll just build a new array (newlist aka _newlist) on-the-fly thus allowing us to simplify the code.

Modifying the current code ...

find_replace_in_list(){
    # $1 = list (array)         : read from
    # $2 = find item (string)   
    # $3 = replace list (array) : read from
    # $4 = newlist (array)      : write to
    # $5 = number of times to match-n-replace (optional; default=1)

    local -n _list=$1
    local ptn=$2
    local -n _replace_list=$3
    local -n _newlist=$4
    local match_count=${5:-1}   # OP can add more logic to validate $5 is a positive integer

    _newlist=()

    for item in "${_list[@]}"
    do
        if [[ "${item}" = "${ptn}" && "${match_count}" -gt 0 ]]
        then
            _newlist+=( "${_replace_list[@]}" )
            (( match_count-- ))
        else
            _newlist+=( "${item}" )
        fi
    done
}

Test #1 (one match & replacement):

list=('a' 'b' 'c' 'd')
find='b'
replace_list=('b1' 'b2' 'b3')
newlist=()
find_replace_in_list list "$find" replace_list newlist
typeset -p newlist

This generates:

declare -a newlist=([0]="a" [1]="b1" [2]="b2" [3]="b3" [4]="c" [5]="d")

Test #2 (no matches found):

list=('a' 'b' 'c' 'd')
find='z'
replace_list=('z1' 'z2' 'z3')
newlist=()
find_replace_in_list list "$find" replace_list newlist
typeset -p newlist

This generates:

declare -a newlist=([0]="a" [1]="b" [2]="c" [3]="d")

Test #3a (one match & replacement):

list=('a' 'b' 'c' 'd' 'c')
find='c'
replace_list=('c7' 'c8' 'c9')
newlist=()
find_replace_in_list list "$find" replace_list newlist
typeset -p newlist

This generates:

declare -a newlist=([0]="a" [1]="b" [2]="c7" [3]="c8" [4]="c9" [5]="d" [6]="c")

Test #3b (allow up to 999 match & replacements):

list=('a' 'b' 'c' 'd' 'c')
find='c'
replace_list=('c7' 'c8' 'c9')
newlist=()
find_replace_in_list list "$find" replace_list newlist 999
typeset -p newlist

This generates:

declare -a newlist=([0]="a" [1]="b" [2]="c7" [3]="c8" [4]="c9" [5]="d" [6]="c7" [7]="c8" [8]="c9")

Find Item in Array / Replace With Array Using Awk?

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