Search results
Results from the WOW.Com Content Network
It is used to parse source code into concrete syntax trees usable in compilers, interpreters, text editors, and static analyzers. [1] [2] It is specialized for use in text editors, as it supports incremental parsing for updating parse trees while code is edited in real time, [3] and provides a built-in S-expression query system for analyzing ...
Encoding support: [15] re2c supports ASCII, UTF-8, UTF-16, UTF-32, UCS-2 and EBCDIC. Flexible user interface: [16] the generated code uses a few primitive operations in order to interface with the environment (read input characters, advance to the next input position, etc.); users can redefine these primitives to whatever they need.
A classic example of a problem which a regular grammar cannot handle is the question of whether a given string contains correctly nested parentheses. (This is typically handled by a Chomsky Type 2 grammar, also termed a context-free grammar.)
In computer programming, a parser combinator is a higher-order function that accepts several parsers as input and returns a new parser as its output. In this context, a parser is a function accepting strings as input and returning some structure as output, typically a parse tree or a set of indices representing locations in the string where parsing stopped successfully.
In computer science, a compiler-compiler or compiler generator is a programming tool that creates a parser, interpreter, or compiler from some form of formal description of a programming language and machine. The most common type of compiler-compiler is called a parser generator. [1] It handles only syntactic analysis.
let the input be a string I consisting of n characters: a 1... a n. let the grammar contain r nonterminal symbols R 1... R r, with start symbol R 1. let P[n,n,r] be an array of real numbers. Initialize all elements of P to zero. let back[n,n,r] be an array of backpointing triples.
When using packrat parsing and memoization, it's noteworthy that the parsing function for each nonterminal is solely based on the input string. It does not depend on any information gathered during the parsing process. Essentially, memoization table entries do not affect or rely on the parser's specific state at any given time. [8]
A parsing expression language is a set of all strings that match some specific parsing expression. [1]: Sec.3.4 A parsing expression grammar is a collection of named parsing expressions, which may reference each other. The effect of one such reference in a parsing expression is as if the whole referenced parsing expression was given in place of ...