2016/09/17 by Nicolas Laurent, Laurent, Nicolas, Kim Mens +1
Computer Science · #D.3.4 #Distributed systems and fault tolerance #FOS: Computer and information sciences #Formal Methods in Verification #Programming Languages (cs.PL) #Software Testing and Debugging Techniques #cs.PL
paper · pdf · doi:10.48550/arxiv.1609.05365
To appear in SLE 2016
arxiv created 2016/09/17 · openalex publication_date 2016/09/17 · arxiv updated 2016/09/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Historically, true context-sensitive parsing has seldom been applied to programming languages, due to its inherent complexity. However, many mainstream programming and markup languages (C, Haskell, Python, XML, and more) possess context-sensitive features. These features are traditionally handled with ad-hoc code (e.g., custom lexers), outside of the scope of parsing theory. Current grammar formalisms struggle to express context-sensitive features. Most solutions lack context transparency: they make grammars hard to write, maintain and compose by hardwiring context through the entire grammar. Instead, we approach context-sensitive parsing through the idea that parsers may recall previously matched input (or data derived therefrom) in order to make parsing decisions. We make use of mutable parse state to enable this form of recall. We introduce principled stateful parsing as a new transactional discipline that makes state changes transparent to parsing mechanisms such as backtracking and memoization. To enforce this discipline, users specify parsers using formally specified primitive state manipulation operations. Our solution is available as a parsing library named Autumn. We illustrate our solution by implementing some practical context-sensitive grammar features such as significant whitespace handling and namespace classification.