Implementation of A Visual Language CQL Interpreter

Because the basic morpheme of visual program is not the common character, the compiler or interpreter of the language is different from that of the program in a common high-level language. In order to implement the interpreter of the database's icon querying language efficiently, the analytical tree of cards is introduced in the implementation. We make use of the 2-dimensional regulating metho, and define the internal storage mechanism of the icon program to meet the need of the pattern analysis, grammatical and semantic analysis. At the same time, temp-cards are used to solve the compiling problem of complex sentence with embedded structure.