Modularizing complex XML data for generation and extraction

A mechanism is provided for creating modules from an XML schema. The mechanism includes creating a syntax tree from a sample XML fragment of the XML schema, creating a module with a list of parameters based on the syntax tree, identifying variable pieces of information in the syntax tree to be inserted in the list of parameters with a variable sign, and inserting the variable information into the list of parameters. The mechanism includes inserting another module in the syntax tree of the module, in which the other module corresponds to another sample XML fragment and has another list of parameters, and identifying the other module with the variable sign in the syntax tree of the module. The mechanism includes inserting the other module into the list of parameters of the module in which the other module to serve as a parameter, and providing an option for constraining the module.