# Write plain JSON? Standard JSON without metadata for deserialization
	#
	# If `false`, the default, serialize to support deserialization:
	#
	# * Write metadata, including the types of the serialized objects so they can
	#   be deserialized to their original form using `JsonDeserializer`.
	# * Use references when an object has already been serialized so to not duplicate it.
	# * Support cycles in references.
	# * Preserve the Nit `Char` and `Byte` types as special objects.
	# * The generated JSON is standard and can be read by non-Nit programs.
	#   However, some Nit types are not represented by the simplest possible JSON representation.
	#   With the added metadata, it can be complex to read.
	#
	# If `true`, serialize for other programs:
	#
	# * Nit objects are serialized to pure and standard JSON so they can
	#   be easily read by non-Nit programs and humans.
	# * Nit objects are serialized for every references, so they can be duplicated.
	#   It is easier to read but it creates a larger output.
	# * Does not support cycles, will replace the problematic references by `null`.
	# * Does not serialize the metadata needed to deserialize the objects
	#   back to regular Nit objects.
	# * Keys of Nit `HashMap` are converted to their string representation using `to_s`.
	var plain_json = false is writable