Repeating same rules for multiple lines ANTLR

Question

I wanted to know what is the right way to apply the parsing rules for multiple lines using ANTLR. I am using the below rule which works fine for single line statements. I wanted to just repeat this over next lines:

    grammar Condition;


/* Parser Rules */

condition : (expr+)? EOF;
expr
    : expr And expr         # andExpr
    | expr Or expr          # orExpr
    | LPar expr RPar        # parExpr
    | prop MIN Numerical expr       # eqExpr
    | prop some expr        # someExpr
    | prop only expr        # onlyExpr
    | prop value dataValue      # valueExpr
    | id                    # idExpr
    | not id                    # idExpr
    ;

id : Identifier;
prop:Identifier;
dataValue:Identifier;

/* Lexical Tokens */

And : 'AND';
Or : 'OR';
LPar : '(';
RPar : ')';
Equals : '=';
some : 'some';
only : 'only';
MIN : 'MIN';
value:'value';
not:'not';
NEWLINE: ('\n') { skip(); };

Numerical : [1-9] [0-9]*;
Data
    : [true]
    | [false]
    | [A]
    | [B]
    | [C]
    | [D]
    ;

// Using generic identifier tokens so that better warnings can be given in later passes.
Identifier : [a-zA-Z_] [a-zA-Z0-9_]*;

// Skip parsing of whitespace but save on hidden channel to enable retrieval of original string.
WhiteSpace : [ \t\r\n]+ -> channel(HIDDEN);

// Invalid character rule is used so that the lexer pass never fails.
InvalidChar : .;

The above grammar gives correct results while testing, but when I try to use visitor it consume each token, it throws the below error :

line 2:0 extraneous input 'SafetyGoal' expecting {, 'AND', 'OR'}

Any suggestions?

EDIT Below is the code I am using to read the input file and call the visitor code:

Stream<String> stream = Files.lines( Paths.get("C:\\test\\RulesTest.txt"), StandardCharsets.UTF_8);
stream.forEach(s -> contentBuilder.append(s).append("\n"));
String input=contentBuilder.toString();
InputStream inStream = new ByteArrayInputStream(input.getBytes(StandardCharsets.UTF_8));
org.antlr.v4.runtime.ANTLRInputStream in=new org.antlr.v4.runtime.ANTLRInputStream(inStream);
System.out.println("These are the lines:"+contentBuilder);
ConditionLexer lexer=new ConditionLexer(in);
org.antlr.v4.runtime.CommonTokenStream tokens= new org.antlr.v4.runtime.CommonTokenStream(lexer);
ConditionParser parser=new ConditionParser(tokens);
ParseTree tree=parser.expr();
MyVisitor vis=new MyVisitor();
vis.visit(tree);

The MyVisitor basically contains the same code as generated by the ANTLR, where I am storing the results as it parses.

Answer 1

ParseTree tree=parser.expr();

You're invoking the expr rule, which only matches a single expression. Your condition rule is the one that matches multiple expressions, so you should invoke that one instead.

Answer 2

Your Data rule is wrong: [true] matches a single character (t, r, u or e). Do this instead:

Data
    : 'true'
    | 'false'
    | [A]
    | [B]
    | [C]
    | [D]
    ;

And testResult value true is not matched by your alternative prop value dataValue because dataValue looks like this:

dataValue : Identifier;

where it should look like this (I'm guessing):

dataValue : Identifier | Data;

When I change your grammar as indicated above and parse the input:

(FSR AND testedBy some (testResult value true)) 
SafetyGoal AND (fulfills some (not NR) OR fulfilledBy some NR)

I get the following parse tree: