Top down parsing

Part 1 of ebook "Compiler design in C" presents the following content: basic concepts; representing computer languages; a recursive-descent expression compiler; input and lexical analysis; context-free grammars; top-down parsing; bottom-up parsing; sentences, phrases, and context-free grammars; ambiguous grammars; augmented grammars and table-driven parsers;...

462p dieptieuung 14-07-2023 9 5   Download

Part 1 of book "Compiler Construction" provide students with knowledge about: language and syntax; regular languages; analysis of context-free languages; attributed grammars and semantics; the programming language Oberon-0; a parser for Oberon-0; consideration of context specified by declarations; a RISC architecture as target; expressions and assignments;...

60p britaikridanik 05-07-2022 11 3   Download

Part 1 of book "Compilers: Principles, Techniques, and Tools (Second Edition)" provide students with knowledge about: background issues in computer architecture and programming-language principles; develops a miniature compiler and introduces many of the important concepts; lexical analysis, regular expressions, nite-state machines, and scanner-generator tools; the major parsing methods, top-down (recursive-descent, LL) and bottom-up (LR and its variants);...

529p britaikridanik 05-07-2022 9 2   Download

Lecture Compiler construction: Lesson 13 - Sohail Aslam. The main topics covered in this chapter include: parsing techniques, top-down parsers, bottom-up parsers, top-down parsing algorithm, expression grammar, left recursion, pick a production and try to match the input,...

63p youzhangjing_1909 28-04-2022 14 1   Download

Lecture Theory of Automata: Lesson 44. The main topics covered in this chapter include: decidability, whether a CFG generates certain string (emptiness), whether a nonterminal is used in the derivation of some word (uselessness), whether a CFL is finite (finiteness), whether the given string is generated by the given CFG (membership), parsing techniques, top down parsing,...

43p wangziyi_1307 26-04-2022 10 2   Download

Nội dung bài giảng chương 3 giúp người học: Nắm được vai trò của giai đoạn phân tích cú pháp; văn phạm phi ngữ cảnh (context- free grammar),cách phân tích cú pháp từ dưới lên- từ trên xuống (top-down and bottom-up parsing); bộ phân tích cú pháp LR. Mời các bạn cùng tham khảo.

60p thiendiadaodien_7 12-02-2019 363 18   Download

In computer science, a recursive descent parser is a kind of top-down parser built from a set of mutually recursive procedures (or a non-recursive equivalent) where each such procedure usually implements one of the productions of the grammar. In this lecture will introduce recursive descent (RD) parser. Inviting you to refer for more detail.

22p youcanletgo_02 07-01-2016 38 2   Download

In this chapter, students will be able to understand: Recursive-descent parsing, left recursion, eliminating left recursion, left recursion - not immediate, top-down parsing, backtracking, drawbacks in recursive descent parser,...and another content.

31p youcanletgo_02 07-01-2016 33 2   Download

Natural language systems based on Categorial Unification Grammar (CUG) have mainly employed bottomup parsing algorithms for processing. Conventional prediction techniques to improve the efficiency of the • parsing process, appear to fall short when parsing CUG. Nevertheless, prediction seems necessary when parsing grammars with highly ambiguous lexicons or with noncanonical categorial rules. In this paper we present a lexicalist prediction technique for CUG and show thai this may lead to considerable gains in efficiency for both bottom-up and top-down parsing. ...

6p buncha_1 08-05-2013 51 1   Download

In this paper a bidirectional parser for Lexicalized Tree Adjoining Grammars will be presented. The algorithm takes advantage of a peculiar characteristic of Lexicalized TAGs, i.e. that each elementary tree is associated with a lexical item, called its anchor. The algorithm employs a mixed strategy: it works bottom-up from the lexical anchors and then expands (partial) analyses making top-down predictions.

6p buncha_1 08-05-2013 50 2   Download

We propose a parser for constraintlogic grammars implementing HPSG that combines the advantages of dynamic bottom-up and advanced topdown control. The parser allows the user to apply magic compilation to specific constraints in a grammar which as a result can be processed dynamically in a bottom-up and goal-directed fashion. State of the art top-down processing techniques are used to deal with the remaining constraints. We discuss various aspects concerning the implementation of the parser as part of a grammar development system. ...

8p bunthai_1 06-05-2013 45 2   Download

Myanmar language and script are unique and complex. Up to our knowledge, considerable amount of work has not yet been done in describing Myanmar script using formal language theory. This paper presents manually constructed context free grammar (CFG) with “111” productions to describe the Myanmar Syllable Structure. We make our CFG in conformity with the properties of LL(1) grammar so that we can apply conventional parsing technique called predictive top-down parsing to identify Myanmar syllables. We present Myanmar syllable structure according to orthographic rules. ...

6p bunthai_1 06-05-2013 59 2   Download

In this paper, we present a novel approach to integrate speech recognition and rulebased machine translation by lattice parsing. The presented approach is hybrid in two senses. First, it combines structural and statistical methods for language modeling task. Second, it employs a chart parser which utilizes manually created syntax rules in addition to scores obtained after statistical processing during speech recognition. The employed chart parser is a unification-based active chart parser. It can parse word graphs by using a mixed strategy instead of being bottom-up or top-down only.

9p bunthai_1 06-05-2013 49 2   Download

Parallel Multiple Context-Free Grammar (PMCFG) is an extension of context-free grammar for which the recognition problem is still solvable in polynomial time. We describe a new parsing algorithm that has the advantage to be incremental and to support PMCFG directly rather than the weaker MCFG formalism. The algorithm is also top-down which allows it to be used for grammar based word prediction.

8p bunthai_1 06-05-2013 34 2   Download

A specialized transition network mechanism, the interruptable transition n e t w o r k (ITN) is used to p e r f o r m the last of three stages in a m u l t i p r o c e s s o r s y n t a c t i c parser. This approach can be seen as an exercise in implementing a parsing procedure of the active chart parser family. Most of the ATN parser implementations use the left-to-right top-down chronological backtracking control structure (cf. Bates, 1978 for discussion).

5p bungio_1 03-05-2013 48 1   Download

This brief paper, which is itself an extended abstract for a forthcoming paper, describes a metric that can be easily computed during either b o t t o m - u p or top-down construction of a parse tree for ranking the desirability of alternative parses. In its simplest form, the metric tends to p r e f e r trees in which constituents are pushed as far down a s possible, but by appropriate modification of a c o n s t a n t in the formula other behavior can be obtained also. This paper includes an...

3p bungio_1 03-05-2013 39 3   Download

On the basis of work in [8] for nondeterministic left-to-right parsing, we trace here a theory of head-driven parsing going from crude top-down and head-corner to more sophisticated solutions, in the attempt to successively make more deterministic the behaviour of head-driven methods. Finally, we propose an original generalization of headdriven parsing, allowing a more detailed specification of the order in which elements of a right-hand side are to be processed.

8p bunmoc_1 20-04-2013 38 2   Download

This paper examines efficient predictive broadcoverage parsing without dynamic programming. In contrast to bottom-up methods, depth-first top-down parsing produces partial parses that are fully connected trees spanning the entire left context, from which any kind of non-local dependency or partial semantic interpretation can in principle be read. We contrast two predictive parsing approaches, topdown and left-corner parsing, and find both to be viable.

8p bunrieu_1 18-04-2013 46 2   Download

The paper presents a tabular interpretation for a kind of 2-Stack Automata. These automata may be used to describe various parsing strategies, ranging from purely top-down to purely bottom-up, for LIGs and TAGs. The tabular interpretation ensures, for all strategies, a time complexity in O(n 6) and space complexity in O(n 5) where n is the length of the input string.

7p bunrieu_1 18-04-2013 36 2   Download

This paper presents empirical studies and closely corresponding theoretical models of the performance of a chart parser exhaustively parsing the Penn Treebank with the Treebank’s own CFG grammar. We show how performance is dramatically affected by rule representation and tree transformations, but little by top-down vs. bottom-up strategies.

8p bunrieu_1 18-04-2013 52 4   Download