Examples with ErrorNode org.antlr.v4.runtime.tree.ErrorNode used on opensource projects

Example 21 with ErrorNode

use of org.antlr.v4.runtime.tree.ErrorNode in project antlr4 by antlr.

the class Parser method consume.

/**
 * Consume and return the {@linkplain #getCurrentToken current symbol}.
 *
 * <p>E.g., given the following input with {@code A} being the current
 * lookahead symbol, this function moves the cursor to {@code B} and returns
 * {@code A}.</p>
 *
 * <pre>
 *  A B
 *  ^
 * </pre>
 *
 * If the parser is not in error recovery mode, the consumed symbol is added
 * to the parse tree using {@link ParserRuleContext#addChild(TerminalNode)}, and
 * {@link ParseTreeListener#visitTerminal} is called on any parse listeners.
 * If the parser <em>is</em> in error recovery mode, the consumed symbol is
 * added to the parse tree using {@link #createErrorNode(ParserRuleContext, Token)} then
 * {@link ParserRuleContext#addErrorNode(ErrorNode)} and
 * {@link ParseTreeListener#visitErrorNode} is called on any parse
 * listeners.
 */
public Token consume() {
    Token o = getCurrentToken();
    if (o.getType() != EOF) {
        getInputStream().consume();
    }
    boolean hasListener = _parseListeners != null && !_parseListeners.isEmpty();
    if (_buildParseTrees || hasListener) {
        if (_errHandler.inErrorRecoveryMode(this)) {
            ErrorNode node = _ctx.addErrorNode(createErrorNode(_ctx, o));
            if (_parseListeners != null) {
                for (ParseTreeListener listener : _parseListeners) {
                    listener.visitErrorNode(node);
                }
            }
        } else {
            TerminalNode node = _ctx.addChild(createTerminalNode(_ctx, o));
            if (_parseListeners != null) {
                for (ParseTreeListener listener : _parseListeners) {
                    listener.visitTerminal(node);
                }
            }
        }
    }
    return o;
}

Example 22 with ErrorNode

use of org.antlr.v4.runtime.tree.ErrorNode in project antlr4 by antlr.

the class ParserRuleContext method addErrorNode.

/**
 * Add a child to this node based upon badToken.  It
 *  creates a ErrorNodeImpl rather than using
 *  {@link Parser#createErrorNode(ParserRuleContext, Token)}. I'm leaving this
 *  in for compatibility but the parser doesn't use this anymore.
 */
@Deprecated
public ErrorNode addErrorNode(Token badToken) {
    ErrorNodeImpl t = new ErrorNodeImpl(badToken);
    addAnyChild(t);
    t.setParent(this);
    return t;
}

Example 23 with ErrorNode

use of org.antlr.v4.runtime.tree.ErrorNode in project antlr4 by antlr.

the class ParserRuleContext method copyFrom.

/**
 * COPY a ctx (I'm deliberately not using copy constructor) to avoid
 *  confusion with creating node with parent. Does not copy children
 *  (except error leaves).
 *
 *  This is used in the generated parser code to flip a generic XContext
 *  node for rule X to a YContext for alt label Y. In that sense, it is
 *  not really a generic copy function.
 *
 *  If we do an error sync() at start of a rule, we might add error nodes
 *  to the generic XContext so this function must copy those nodes to
 *  the YContext as well else they are lost!
 */
public void copyFrom(ParserRuleContext ctx) {
    this.parent = ctx.parent;
    this.invokingState = ctx.invokingState;
    this.start = ctx.start;
    this.stop = ctx.stop;
    // copy any error nodes to alt label node
    if (ctx.children != null) {
        this.children = new ArrayList<>();
        // reset parent pointer for any error nodes
        for (ParseTree child : ctx.children) {
            if (child instanceof ErrorNode) {
                addChild((ErrorNode) child);
            }
        }
    }
}

Example 24 with ErrorNode

use of org.antlr.v4.runtime.tree.ErrorNode in project antlr4 by antlr.

the class Trees method getNodeText.

public static String getNodeText(Tree t, List<String> ruleNames) {
    if (ruleNames != null) {
        if (t instanceof RuleContext) {
            int ruleIndex = ((RuleContext) t).getRuleContext().getRuleIndex();
            String ruleName = ruleNames.get(ruleIndex);
            int altNumber = ((RuleContext) t).getAltNumber();
            if (altNumber != ATN.INVALID_ALT_NUMBER) {
                return ruleName + ":" + altNumber;
            }
            return ruleName;
        } else if (t instanceof ErrorNode) {
            return t.toString();
        } else if (t instanceof TerminalNode) {
            Token symbol = ((TerminalNode) t).getSymbol();
            if (symbol != null) {
                String s = symbol.getText();
                return s;
            }
        }
    }
    // no recog for rule names
    Object payload = t.getPayload();
    if (payload instanceof Token) {
        return ((Token) payload).getText();
    }
    return t.getPayload().toString();
}