new parameterized mailers example

user_mailer_in_rails_5.rb

class UserMailer < ApplicationMailer
  before_action {
    @email = params[:email]
    @name = params[:name]
    @message = params[:message]
  }

  default to: -> { @email },
          from: -> { "[email protected]" }

  def sign_up
    mail subject: "Confirm your email!"
  end

  def welcome
    mail subject: "Welcome to Example."
  end
end