antlr4

How can I parse a file containing a decimal numbers into a List<double> in C# using ANTLR4? A complete, working example would illustrate how all the pieces go together. The input file looks like this: 12.34 45.67 89.10 TomServo This is an updated version of an older answer to a different question, showing one way to do this task using C# and ANTLR4. The Grammar grammar Values; parse : (number ( LINEBREAK | EOF ) )* ; number : NUMBER ; NUMBER : DIGIT '.' DIGIT ; DIGIT : [0-9]+ ; WS : [ \t] -> channel(HIDDEN) ; LINEBREAK : '\r'? '\n' | '\r' ; The Listener Now the class that implements the

I found an ANTLRv4 Python3 grammer , but it generates a parse-tree, which generally has many useless nodes. I'm looking for a known package to get a Python AST from that parse tree. Does something like this exist? EDIT: Clarification regarding use of the Python ast package: my project is in Java and I need to parse Python files. EDIT 2: By 'AST' I mean http://docs.python.org/2/library/ast.html#abstract-grammar , while by 'parse tree' I mean http://docs.python.org/2/reference/grammar.html . The following could be a start: public class AST { private final Object payload; private final List<AST>

I have a grammar file BoardFile.g4 that has (relevant parts only): grammar Board; //Tokens GADGET : 'squareBumper' | 'circleBumper' | 'triangleBumper' | 'leftFlipper' | 'rightFlipper' | 'absorber' | 'portal' ; NAME : [A-Za-z_][A-Za-z_0-9]* ; INT : [0-9]+ ; FLOAT : '-'?[0-9]+('.'[0-9]+)? ; COMMENT : '#' ~( '\r' | '\n' )*; WHITESPACE : [ \t\r\n]+ -> skip ; KEY : [a-z] | [0-9] | 'shift' | 'ctrl' | 'alt' | 'meta' | 'space' | 'left' | 'right' | 'up' | 'down' | 'minus' | 'equals' | 'backspace' | 'openbracket' | 'closebracket' | 'backslash' | 'semicolon' | 'quote' | 'enter' | 'comma' | 'period' |

Antlr4 has a new class ParseTreeWalker. But how do I use it? I am looking for a minimal working example. My grammar file is 'gram.g4' and I want to parse a file 'program.txt' Here is my code so far. (This assumes ANTLR has run my grammar file and created all of the gramBaseListener , gramLexer , etc etc): import org.antlr.v4.runtime.*; import org.antlr.v4.runtime.tree.*; import static org.antlr.v4.runtime.CharStreams.fromFileName; public class launch{ public static void main(String[] args) { CharStream cs = fromFileName("gram.g4"); //load the file gramLexer lexer = new gramLexer(cs); /

Does anyone know if there is an existing existing ANTLR or IRONY grammar for R? Many thanks. I've built an R grammar for the early access "Honey Badger" ANTLR v4 release, if you'd like to give it a look. See the ANTLR v4 Examples page . Source for v4 is https://github.com/antlr/antlr4 . binary jar here: http://antlr.org/download/antlr-4.0ea-complete.jar For R you want http://www.antlr.org/wiki/download/attachments/28049418/R.g4 I'd guess a good place to look would be R to C Compiler (RCC) that was developed by John Garvin at Rice 来源： https://stackoverflow.com/questions/5705564/is-there-an