Formal language

About: Formal language is a research topic. Over the lifetime, 5763 publications have been published within this topic receiving 154114 citations.

Model theory for extended modal languages

Abstract: 207

Concurrency and discrete event control

Abstract: Much of discrete event control theory has been developed within the framework of automata and formal languages. An alternative approach inspired by the theories of process-algebra as developed in the computer science literature is presented. The framework, which rests on a new formalism of concurrency, can adequately handle nondeterminism and can be used for analysis of a wide range of discrete event phenomena. >

Enforcing strict model-view separation in template engines

Abstract: The mantra of every experienced web application developer is the same: thou shalt separate business logic from display. Ironically, almost all template engines allow violation of this separation principle, which is the very impetus for HTML template engine development. This situation is due mostly to a lack of formal definition of separation and fear that enforcing separation emasculates a template's power. I show that not only is strict separation a worthy design principle, but that we can enforce separation while providing a potent template engine. I demonstrate my StringTemplate engine, used to build jGuru.com and other commercial sites, at work solving some nontrivial generational tasks.My goal is to formalize the study of template engines, thus, providing a common nomenclature, a means of classifying template generational power, and a way to leverage interesting results from formal language theory. I classify three types of restricted templates analogous to Chomsky's type 1..3 grammar classes and formally define separation including the rules that embody separation.Because this paper provides a clear definition of model-view separation, template engine designers may no longer blindly claim enforcement of separation. Moreover, given theoretical arguments and empirical evidence, programmers no longer have an excuse to entangle model and view.

Gröbner methods for representations of combinatorial categories

Abstract: Given a category C of a combinatorial nature, we study the following fundamental question: how does the combinatorial behavior of C affect the algebraic behavior of representations of C? We prove two general results. The first gives a combinatorial criterion for representations of C to admit a theory of Grobner bases. From this, we obtain a criterion for noetherianity of representations. The second gives a combinatorial criterion for a general “rationality” result for Hilbert series of representations of C. This criterion connects to the theory of formal languages, and makes essential use of results on the generating functions of languages, such as the transfer-matrix method and the Chomsky–Schutzenberger theorem. Our work is motivated by recent work in the literature on representations of various specific categories. Our general criteria recover many of the results on these categories that had been proved by ad hoc means, and often yield cleaner proofs and stronger statements. For example: we give a new, more robust, proof that FI-modules (originally introduced by Church–Ellenberg–Farb), and a family of natural generalizations, are noetherian; we give an easy proof of a generalization of the Lannes–Schwartz artinian conjecture from the study of generic representation theory of finite fields; we significantly improve the theory of ∆modules, introduced by Snowden in connection to syzygies of Segre embeddings; and we establish fundamental properties of twisted commutative algebras in positive characteristic.