Improve specs and guards in GenEvent (#5331)
Improve specs and guards in GenEvent (#5331)


lexmag/elixir,pedrosnk/elixir,lexmag/elixir,antipax/elixir,kelvinst/elixir,joshprice/elixir,ggcampinho/elixir,beedub/elixir,pedrosnk/elixir,gfvcastro/elixir,gfvcastro/elixir,michalmuskala/elixir,kelvinst/elixir,kimshrier/elixir,antipax/elixir,elixir-lang/elixir,kimshrier/elixir,ggcampinho/elixir,beedub/elixir