Install latest version of Go in Linux

install-go.sh

#!/bin/env bash

set -o errexit
set -o pipefail
set -o nounset

export INSTALL_GO_SH="$0"

main() {
    if [[ "${1:-}" =~ ^(-v|--verbose)$ ]]; then
        set -o errexit
    fi

    # Force run with bash.
    if [ -z "${BASH_VERSION:-}" ]; then
        exec /bin/bash "${INSTALL_GO_SH}" "$@"
        exit
    fi
    
    local VER
    local ARCH
    local FILE

    echo "INFO: Fetching latest Go version ..." 1>&2
    typeset VER="$(curl -s 'https://golang.org/dl/' | grep -m 1 -o 'go1\.[0-9.]\+')"
    echo "INFO: Found latest version='${VER}'" 1>&2
    if uname -m | grep -q 64; then
        typeset ARCH=amd64
    else
        typeset ARCH=386
    fi
    typeset FILE="${VER}.linux-${ARCH}"
    echo "INFO: Installing '${FILE}' ..." 1>&2

    curl -# https://storage.googleapis.com/golang/$FILE.tar.gz \
        | tar -C /usr/local -xzf -

    if ! grep -q '^# Go Paths .*$' "${HOME}/.bashrc"; then
        echo "
# Go Paths (Added on: $(date -u))
export GOPATH=\"\${HOME}/go\"
export PATH=\"\${PATH}:/usr/local/go/bin:\${GOPATH}/bin\"" >> ~/.bashrc
    fi

    . ~/.bashrc
    echo "INFO: Go is installed and your GOPATH is '$HOME/go'" 1>&2
    echo "INFO: Please reload this shell or enter the command '. ~/.bash_profile'" 1>&2
}

if