The NIST EXPRESS toolkit is a software library for building EXPRESS-related tools. The toolkit was previously released in 1991, based on ISO TC184/SC4 N14 (familiarly called "EXPRESS N14"). The current release is based on Draft International Standard (DIS) 10303-11 (N151) and while the philosophical underpinnings are similar, much of the interface has changed significantly. This paper describes changes that must be made to existing applications so that they can work with the new toolkit. This paper should be read by anyone maintaining software based upon the NIST EXPRESS toolkit. This paper will also provide insight to people interested in the internals of EXPRESS implementations and some of the ways they have changed over time due to experience and the different EXPRESS specifications. Keywords: compiler, EXPRESS; implementation; National PDES Testbed; PDES; STEP Context The PDES (Product Data Exchange using STEP) activity is the United States' effort in support of the Standard for ...

The National Institute of Standards and Technology (NIST) has built numerous software toolkits and applications for manipulating STEP and EXPRESS data. The NIST EXPRESS Server is a computational facility at NIST, which provides the ability to run toolkit-based applications remotely without installing them locally. EXPRESS Schemas and other data files are e-mailed to the server. The server runs the requested applications on the files and returns any diagnostics or output, also by e-mail. Applications requiring interaction can either be returned via e-mail so that they can be run locally, or run remotely by telnet or rlogin across the Internet. Access to the EXPRESS Server is available at zero cost to anyone who can send e-mail. No initial registration is required. Use is anonymous by default, however it is possible to use the server as a collaborative testbed in which case results can be immediately shared with other server users. The server is capable of restricting file access to one ...

The National Institute of Standards and Technology (NIST) has built numerous software toolkits and applications for manipulating STEP and EXPRESS data. These toolkits are traditionally used as compiled libraries which are linked to other compiled modules. This paper describes a binding allowing the toolkit interfaces to be called from interpreted scripts. This significantly reduces the time required to construct and compile new applications. An X11 extension allows the construction of graphic elements, providing easy creation and integration of existing applications into X graphic user interfaces. We describe how the combination of bindings has been used to construct a STEP Application Protocol Development Environment. Keywords: Tcl; Tk; EXPRESS; Object Oriented; National PDES Testbed; PDES; STEP; APDE; Development Environment Reprinted from Proceedings of the EXPRESS User Group Workshop (EUG `95), Grenoble, France, October 21-22, 1995. An Object-Oriented Tcl/Tk Binding for Interpr...