ANTLR4 in depth
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Vladimir Kozhaev offers freelance development services for programming languages and tools, including domain specific language development using ANTLR. ANTLR is a powerful parser generator that can be used to build languages, tools, and frameworks from a grammar specification. It generates a parser that builds parse trees from structured text or binary files. Key features of ANTLR include support for multiple programming languages as code generation targets, an active development community, and good documentation resources.
ANTLR4 in depth
- 1. Vladimir Kozhaev ● Freelancer ● Development of programming languages and development tools. ● If you need to develop a domain specific language, IDE based on Eclipse or Inellij Idea, parser, compiler do not heistate to ask me. ● email:vkozhaev@gmaill.com, skype:vladimir.kozhaev blog:http://gamesdevandmath.bl ogspot.com
- 2. ● ANTLR 4, DSL development in depth
- 3. ANTLR overview ● ANTLR (ANother Tool for Language Recognition) is a powerful parser generator for reading, processing, executing, or translating structured text or binary files. It's widely used to build languages, tools, and frameworks. From a grammar, ANTLR generates a parser that can build and walk parse trees. ● Now avaiable version 4.5.3 ● Java, C#, JavaScript, Python2, Python3 targets ● Some alternatives:JFlex,JLex,CookCC,AustenX
- 4. Why ANTLR? ● Developed with java ● Actively developing project ● Opensource ● Vide range of the tools and target languages ● Existing community ● Good book: The Definitive ANTLR 4 Reference by Terence Parr ● A lot of the syntax sugar:left recursion, right associativity etc
- 5. What is ANTLR ● Parsers(for example log files) ● Translators(from JSON to XML, pseudocode to Java) ● Domain Specific Languages(DSL)
- 10. Lexems vs Fragments where is a difference? ● A fragment will never be counted as a token, it only serves to simplify a grammar. ● They need to be referenced from a lexer rule ● Matching a NUMBER will always return a NUMBER to the lexer, regardless of if it matched "1234", "0xab12", or "0777"
- 11. Priority Rules Several lexer rules can match the same input text. In that case, the token type will be chosen as follows: ● First, select the lexer rule which matches the longest input ● If several lexer rules match the same input length, choose the first one, based on definition order
- 13. Error recovering
- 14. Visitors,Listeners,Actions ● Example 1, with visitor ● Example 2, with listener ● Example 3, with embeded action ● See https://github.com/vladimirkozhaev/https--- github.com-vladimirkozhaev-calc_antlr
- 15. Lexer vs parser rules ● Lexer vs parser, question two steps with the same sence ● Lexer rules are used to split text on the tokens ● Parser rules - for higher level parsing
- 16. Right associativity expr : expr '^'<assoc=right> expr // ^ operator is right associative | INT ;
- 19. Questions ● Ask me please?