Technical Reports (CIS)

Document Type

Technical Report

Date of this Version

August 1972


University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-73-01.


The Data Description Language Processor, designed by J. A. Ramirez, is the compiler for a modified version of the Data Description Language (DDL), written by D. P. Smith.

Two main phases exist in the DDL Processor:

1) The Syntactic Analysis phase and

2) The Code Generation phase

The former phase checks the DDL source for local and global syntactic flaws before passing control to the latter. In order to speed up execution of phase 2, internal tables (one symbol and several data tables), containing encoded versions of the DDL source input, are constructed. The tables, created during syntax analysis, will facilitate global syntax checking (verifying all DDL statement references to be valid), and will permit code generation to operate more quickly by providing it with the "essence" of the source data and, hence, negate the necessity of a second pass over the source input.



Date Posted: 19 November 2007