open Bistro

class type nhx = object
  inherit text_file
  method format : [`nhx]
end

class type nw = object
  inherit text_file
  method format : [`nw]
end

class type diffsel_tree = object
  inherit text_file
  method format : [`diffsel_tree]
end

class type topological_tree = object
  inherit text_file
  method format : [`topological_tree]
end

class type nucleotide_fasta = object
  inherit fasta
  method alphabet : [`Nucleotide]
end

class type aminoacid_fasta = object
  inherit fasta
  method alphabet : [`Aminoacid]
end

class type nucleotide_phylip = object
  inherit text_file
  method format : [`Nucleotide]
end
class type aminoacid_phylip = object
  inherit text_file
  method format : [`Aminoacid]
end