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The NIST STEP Class Library STEP Into the Future



Michael Mclay, KC Morris


This paper describes a C++ class library that implements the Standard for the Exchange of Product Model Data (STEP). The STEP Class Library (SCL) is under development at the National Institute of Standards and Technology as part of the National PDES Testbed. It provides a core set of classes for tools used to validate the STEP conceptual data models and for STEP based application prototypes. The library is also intended to facilitate the development of STEP compliant applications. The current version of the library provides a file exchange mechanism based on protocol defined by STEP. Consequently, users of the class library will not have to create an input/output mechanism for STEP. This paper provides an introduction to STEP and the conceptual schema language, Express, in which STEP models are defined. The supporting classes that provide the STEP complaint input/output mechanism and the mapping between the Express specification and the C++ classes are described. The paper concludes with descriptions of some applications that use the class library and a discussion of future directions for the library.
Proceedings Title
Proceedings of the C++ at Work '90 Conference
Conference Location


computational data, PDES, product model data, SCL, STEP, STEP Class Library


McLay, M. and Morris, K. (1990), The NIST STEP Class Library STEP Into the Future, Proceedings of the C++ at Work '90 Conference, , USA, [online], (Accessed April 14, 2024)
Created July 31, 1990, Updated October 12, 2021