MDDL: The Math Data Description Language and MathHub data hosting.

The MDDL allows mathematical data set creators to describe the meaning of mathematical objects in a data set and their database encoding declaratively and then generate data tables, user interfaces, and update facilities from them. MDDL uses

All of these are regular flexiformal theories, that can make use of the existing MathHub libraries. Consequently, a mathematical data colletions are regular MathHub Library with MDDL schema theories.

An example of a MDDL-based schema collection can be seen in MathHub (MDDL, VT, and the generated data collection Symmetric Objects)