if test -e /path/to/file
    command/alias
end

if test -e /path/to/file1; or test -e /path/to/file2
    command/alias
end

if test -x /usr/bin/eza -o -x $HOME/.cargo/bin/eza
    # Define eza-based commands
    function ls
        command eza -a --color=always --group-directories-first --icons $argv
    end

    function lr
        command eza -al --color=always --group-directories-first --icons $argv
    end

    function ll
        command eza -l --color=always --group-directories-first --icons $argv
    end

    function lt
        command eza -aT --color=always --group-directories-first --icons $argv
    end

    function l.
        command eza -ald --color=always --group-directories-first --icons .* $argv
    end

    function lf
        command eza -aD --color=always --group-directories-first --icons $argv
    end
else
    # Define dummy functions that remind user to install eza
    for cmd in lr ll lt l. lf
        function $cmd
            echo "The command 'eza' is not installed. Please install 'eza' to use this: https://github.com/eza-community/eza"
        end
    end
end