1. A method for transformation validation implemented by a data processing system, comprising: loading, in a data processing system, a first language definition and a second language definition; loading, in the data processing system, a transformation definition corresponding to the first language definition and the second language definition, wherein the transformation definition maps a first construct of the first language definition to a second construct of the second language definition; loading, in the data processing system, a validation rule definition, wherein the validation rule definition defines a successful transformation between the first construct and the second construct and indicates whether the transformation definition produces a valid transformation between the first construct and the second construct; and applying the validation rule definition to the transformation definition by the data processing system to produce a validation result indicating whether the transformation definition produces a valid transformation between the first language definition and the second language definition; and storing the validation result in the data processing system.