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NIST Express Toolkit: Requirements for Improvements



Donald E. Libes, James E. Fowler


The NIST EXPRESS toolkit is a software library for building EXPRESS-related tools. This paper is one in a series describing the latest version of the toolkit. This document describes shortcomings of previous versions of the toolkit, requirements for improvement, and a recommended approach for addressing those requirements. A background knowledge of EXPRESS and the EXPRESS toolkit is presumed as well as a rudimentary grasp of basic compiler construction techniques.
NIST Interagency/Internal Report (NISTIR) - 5212
Report Number


compiler, Express, implementation, National PDES Testbed, PDES, STEP


Libes, D. and Fowler, J. (1993), NIST Express Toolkit: Requirements for Improvements, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed July 14, 2024)


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Created December 31, 1992, Updated October 12, 2021