msignature = new MSignature(mparameters, ret_type)
mpropdef.msignature = msignature
mpropdef.is_abstract = self.get_single_annotation("abstract", modelbuilder) != null
msignature = new MSignature(mparameters, ret_type)
mpropdef.msignature = msignature
mpropdef.is_abstract = self.get_single_annotation("abstract", modelbuilder) != null