Parsing/parsers

Command-line parser, a component to read commands and parse them against a command grammar... 

The rule is parsed in a top-down fashion(l6) using a BNF driven parser according to the explicit grammar, a portion of which is shown in Figure 5. This is a fairly simple context free grammar, written in the BNF (Backus Normal Form) style.(17) A condensed version of the parse tree for the sample rule is shown in Figure 6. Semantic analysis checks for ... 

We expect technical adapters equipped with a COM interface to exist. This enables to parse the interfaces of legacy systems by the existing parser. Furthermore, a model of the COM component according to our modeling formalism can be generated (cf. technical wrapper in Subsect. 5.7.4). In this way, layer 2 is covered by phase 1 of the development process. 

Proper parsing can resolve part-of-speech ambiguity problems that finite state (ie HMM parsers) fail on, such as Example 49 above. 

The first problem that we encounter in parsing is that any simplistic or exhaustive search for the correct set of mles is prohibitively expensive. Parsers can therefore be thought of as search algorithms which find a tree or trees for a sentence in reasonable time. The second problem in parsing is that any non-trivial set of mles will generate more than one parse that fits the input, and in many cases an considerable number of perfectly legal parses will fit the input. A simple example is ... 

The major weakness with this type of parsing is that it only considers syntactic factors, semantics is completely ignored. That is why a parser often returns parses that are correct but seem silly. Some more advanced models of S5mtax do incorporate semantic information [78], [177], [312], but in general most syntax models, especially in engineering, only make use of syntactic rules. 

Define a CFG by hand and use a deterministic search algorithm (i.e. the parser) to find the parse or parses which best fit the input... 

For more compound noun phrases involving three or more words, a C YK parser (see Section 5.5) is used to assign the internal structure to the noun phrase, after which prominence values can be assigned. To resolve ambiguity, a set of heuristics is used to find the best parse. These are ... 

The analysis of an input string by an AGinterpretor jnoceeds in two biases. In the first, c ed syntax analysis, a context-free parser is used to construct a parse tree df the itqmt string, hi Ae second, called semantic analysis, the values df the attributes at the nodes of the parse tree are evaluated and the semantic conditions are tested. 

Specification-based techniques have not succeeded as well in context-sensitive analysis as they have in scanning and parsing. While formal methods for these problems have been developed, their adoption has been slowed by a number of practical problems. Thus, many modern compilers use simple ad hoc methods to perform context-sensitive analysis. In fact, most parser generator systems include substantial support for performing such ad hoc tasks. 

The XML Parser is a simple context-based parser. In each context there are two callback functions that are used for opening and closing markup tags. During the parsing, these functions are called to initialize the RSI array and the safety rule trees. Context switching is performed inside the callback function according to the parsed XML tag. 

The first step GUIsurfer performs is the parsing of the source code. This is achieved by executing a parser and generating an abstract syntax tree. An AST is a formal representation of the abstract syntactical structure of the source code. Moreover, the AST represents the entire code of the application. However, the tool s objective is to process the GUI layer of interactive... 

The parser analyses statement by statement and writes the interface data structures onto the parse tree file. 

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