1. A computer-implemented method to support an object-oriented scripting tool in a markup language environment, comprising: specifying, in a file, a software class in a scripting language using a first tag that is defined in the markup language environment, wherein the software class includes at least one method; referring to the at least one method in a second tag, wherein the second tag is not defined in the markup language environment; using a parser, running on one or more microprocessors, to parse the file; determining the second tag to be an unknown element in the markup language environment, when the parser reaches the second tag in the file; using the second tag as a key to obtain a type definition by checking with a type definition table; and invoking the at least one method.