command to search and replace strings in found files using `ag`

ag_replace.sh

function ag_replace {
    if [ -z "$1" -o $# -eq 1 ]; then
        echo "Usage: ag_replace FROM_STRING TO_STRING [OPTION]..."
        echo
        echo "Replace all occurances of FROM_STRING (a sed-compatible regular"
        echo "expression) with TO_STRING in all files for which ack-grep matches"
        echo "FROM_STRING."
        echo
        echo "Any additional options are passed directly to ack-grep (e.g.,"
        echo " --type=html would only run the substitution on html files)."
        return 1
    fi
    # Escape forward slashes for sed
    FROM_STRING=${1/\//\\/}
    TO_STRING=${2/\//\\/}
    shift 2
    ag -l --print0 "$@" "$FROM_STRING" | xargs -0 -n 1 sed -i '' "s|$FROM_STRING|$TO_STRING|g"
}

example

source ag_replace.sh

ag_replace '"package": "^2.0.1"' '"package": "^2.3.1"'