antlr4

问题 I want to parse plain text comments and look for certain tags within them. The types of tags I'm looking for look like: <name#1234> Where "name" is a [a-z] string (from a fixed list) and "1234" represents a [0-9]+ number. These tags can occur within a string zero or more times and be surrounded by arbitrary other text. For example, the following strings are all valid: "Hello <foo#56> world!" "<bar#1>!" "1 < 2" "+<baz#99>+<squid#0> and also<baz#99>.\n\nBy the way, maybe <foo#9876>" The

问题 We're starting a project where we will need to parse python source files in a C++ application. I've used Antlr2 a while back to generate a few compilers, but this is the first time I'm using Antlr4. It looks like the c++ antlr4 target is fairly active at https://github.com/antlr/antlr4-cpp So, my question is basically what is the status of the Antlr4 C++ target, is it ready to start being used? To use the C++ target, what just grab the Antlr4 source, and copy the Antlr4-cpp into this tree and

问题 I've been learning about ANTLR 4 with Terence Parr's The Definitive ANTLR 4 Reference , which I've been following so far using Gradle 2.10 and its built-in ANTLR plugin. However I'm having some trouble getting some code which I adapted from Chapter 4, pp. 38-41 to work properly with my Gradle build script. (The reason I'm using Gradle, rather than ANTLR directly, is because I want to eventually integrate ANTLR into a Java web application which I'm making for my dissertation, and I'd strongly

问题 How to flatten a ParserRuleContext with subtrees into an array of tokens? The ParserRuleContext.getTokens(int ttype) looks good. but what is ttype ? Is it token type? What value to use if I want to include all token types? 回答1: ParserRuleContext.getTokens(int ttype) only retrieves certain child nodes of a parent: it does not recursively go into the parent-tree. However, it is easy enough to write yourself: /** * Retrieves all Tokens from the {@code tree} in an in-order sequence. * * @param

问题 I'm parsing a script language that defines two types of statements; control statements and non control statements. Non control statements are always ended with ';' , while control statements may end with ';' or EOL ('\n'). A part of the grammar looks like this: script : statement* EOF ; statement : control_statement | no_control_statement ; control_statement : if_then_control_statement ; if_then_control_statement : IF expression THEN end_control_statment ( statement ) * ( ELSEIF expression

问题 If you look at the ObjectiveC antlr v3 grammars (http://www.antlr3.org/grammar/1212699960054/ObjectiveC2ansi.g), and many of the other popular grammars out there they do a similar structure to this for solving conditionals conditional_expression : logical_or_expression ('?' logical_or_expression ':' logical_or_expression)? ; constant_expression : conditional_expression ; logical_or_expression : logical_and_expression ('||' logical_and_expression)* ; logical_and_expression : inclusive_or

问题 I am trying to convert ant ANTLR3 grammar to an ANTLR4 grammar, in order to use it with the antlr4-python2-runtime. This grammar is a C/C++ fuzzy parser. After converting it (basically removing tree operators and semantic/syntactic predicates), I generated the Python2 files using: java -jar antlr4.5-complete.jar -Dlanguage=Python2 CPPGrammar.g4 And the code is generated without any error, so I import it in my python project (I'm using PyCharm) to make some tests: import sys, time from antlr4

问题 I have created new Gradle project, added apply plugin: 'antlr' and dependencies { antlr "org.antlr:antlr4:4.5.3" to build.gradle . Created src/main/antlr/test.g4 file with the following content grammar test; r : 'hello' ID; ID : [a-z]+ ; WS : [ \t\r\n]+ -> skip ; But it doesn't work. No java source files generated (and no error occurred). What I missed? Project is here: https://github.com/dims12/AntlrGradlePluginTest2 UPDATE I found my sample is actually works, but it put code into \build

问题 I am trying to parse a mathematical formula to a subset of LaTeX using ANTLR4. For example it should parse (a+4)/(b*10) to \frac{a+4}{b\cdot 10} . My simple grammar creates a tree like this: Now I am trying to implement parse tree listeners to somehow construct the LaTeX String while the tree is traversed. Here, I am failing because to construct a String like \frac{}{} it has to be built recursively. The parse tree walker, however, visits one tree node after the other (in a breadth-first way

问题 I'm having function with arguments grammer like below lexer and parser: MyFunctionsLexer.g4 lexer grammar MyFunctionsLexer; FUNCTION: 'FUNCTION'; NAME: [A-Za-z0-9]+; DOT: '.'; COMMA: ','; L_BRACKET: '('; R_BRACKET: ')'; WS : [ \t\r\n]+ -> skip; MyFunctionsParser.g4 parser grammar MyFunctionsParser; options { tokenVocab=MyFunctionsLexer; } functions : function* EOF; function : FUNCTION '.' NAME '(' (function | argument (',' argument)*) ')'; argument: (NAME | function); But in parser is