Open Source EXPRESS Parser / News: Recent posts

The Parser now supports the express amendment additions:

- extensible enumerations
- extensible selects
- abstract entities
- generic entites
- subtype constraints
etc.

The template.g, pretty.g and exp2xml.g files have been modified to use the new grammar, so, older ANTLR files should not work anymore.
Anyway, the new grammar is backward compatible with the older one (i.e. the new parser can read Express and ExpressV2 files as well)

This tool based on the express parser can convert STEP Express models to XML text using a specific DTD
(see http://ats.nist.gov/stepmod\)

The last release of the parser features a new tree structure.
Every rule in the grammar now produces a tree node. The type of the node is a token named after the grammar rule.
See source and README.txt for further explanation.

After some discussion with potential users of the parser, we'll keep ANTLR's tree structure, but update the way the AST is built. Express-X rules will be removed in next version.