I have a text file which am parsing through antlr4. Text format Grammar Rules I get this What am i doing wrong and how could i make these rules better? Answer Your example input get properly parsed if you start with the init rule: prints: which looks like this indented: My guess is that the error you’re…
Tag: antlr4
How to get from parse tree to Java class file
I am working on a command-line tool with the following functionality: Parse modified .java files using an extended ANTLR4 Java9 grammar. The syntax in the files is Java, with one modification to the method declaration which includes a purpose, like in this example: public void {marketing} sendEmail() {} Colle…
ANTLR4: How to match extra spaces at the beginning of a line?
I tried to match the extra space at the beginning of the line, but it didn’t work. How to modify the lexer rule to match? TestParser.g4: TestLexer.g4: Text: Java code: The output is as follows: The idea is that when a non-option line is encountered in OPTION_MODE, the mode will pop up, and now when ther…
How to parse Java code in Python using ANTLRv4
I’m trying to parse some Java code in Python using ANTLRv4. I’ve tried to follow this post, but I get the following error: I can’t figure out what I’m doing wrong. The file I’m trying to parse is proper Java, it’s extracted from the docker-maven-plugin package. I’ve t…
How to parse a Clickhouse-SQL statement using ANTRL4?
Objective : Add an additional WHERE clause to any given Clickhouse statement. I’m using the following Antlr grammars to generate Java classes for a lexer & parser. Lexer grammar https://github.com/ClickHouse/ClickHouse/blob/master/utils/antlr/ClickHouseLexer.g4 Parser grammar https://github.com/Clic…
ANTLR4 Return values from a function
Im making a programming language as a project at my University and I’ve run into a problem with adding a return statement in functions. This is my grammar: And here is the custom visitor To help with transferring data I have made classes to carry values and function data. The problem I have atm is when …
Separate definitions of decimal number and word in ANTLR grammar
I’m working on defining a grammar in ANTLR4 which includes words and numbers separately. Numbers are described: and words are described: The simplified grammar below describes the addition between either a word or a letter (and needs to be defined recursively like this): The issue is that when I enter &…
How to instruct the grammar to NOT generate certain methods in the ANTLR listener?
I have this grammar: The listener interface, which ANTLR generates, contains these four methods: Two of them are not needed for me: exitFoo() and enterBar(). Is it possible to tell ANTLR somehow to NOT generate them in the interface? I would actually prefer to find a way to somehow tell the grammar which gram…
Antlr4 Project Directory Structure Issue
I’m trying to set up an Antlr4 project using Java’s package directory structure. The top level directory contains PondParser.g4, PondLexer.g4, and build_script. build_script is expected to build and run the antlr4 test rig Relevant PondParser.g4 header and options: Relevant PondLexer.g4 header and…
How to extract line with syntax error when parsing PlSQL using Antlr4
I am using the grammar file for PlSql from this Github repository. I want to underline the line in plsql file that I parse if it has a syntax error. I have the following snippet to do so: While this works fine in most cases, some scripting languages, like PlSql, need special handling for case-sensitivity. Thi…