A grep with Vim regular expressions

vgrep.sh

#!/bin/bash
vgrep() {
    local re=${1:-^}
    local files=()
    for arg in "${@:2}"; do
        [ -f "${arg}" ] && files+=( "${arg}" )
    done
    if [ -z "${files[*]:1}" ]; then
        vim -Ni NONE -nes <<<"argdo g/${re////\\/}/p" -- "${files[@]}"
    else
        vim -Ni NONE -nes <<END -- "${files[@]}" 2>&1 | sed -e '1d' -e 's/\r$//'
        argdo g/${re////\\/}/verbose echo expand('%').':'.getline('.')
        verbose echo "\n"
END
    fi
}

Companion article at http://glts.github.io/2013/06/08/using-vim-as-grep.html.