ANTLR4 Golang grammar file

Question

I'm getting a warning while trying to create AST tree from golang code line 6:1 no viable alternative at input 'sMap, lMap map[int32]string\r\n\tif' The code I tried,

package dum
func mergeIntStrMap(map1 map[int32]string, map2 map[int32]string) string {

    var sMap, lMap map[int32]string
    return lMap
}

Grammar file I downloaded from [github] https://github.com/antlr/grammars-v4/blob/master/golang/ . Is there any issue in the grammar file or any fix for this. Used code to generate AST(python code),

from antlr4 import *
from GoParser import GoParser
from GoLexer import GoLexer
file = FileStream(f,encoding = 'utf-8')
lexer = GoLexer(file)
token = CommonTokenStream(lexer)
parse = GoParser(token)
trees = parse.sourceFile()

here GoParser and GoLexer files are generated from grammar file.

Thanks in Advance

Answer 1

You either changed something in the grammar file(s), or you did not implement GoParserBase.py correctly, because without changing anything, your example Go code is correctly parsed: