Examples with BlockAST org.antlr.v4.tool.ast.BlockAST used on opensource projects

Example 6 with BlockAST

use of org.antlr.v4.tool.ast.BlockAST in project antlr4 by antlr.

the class ParserFactory method getChoiceBlock.

@Override
public Choice getChoiceBlock(BlockAST blkAST, List<CodeBlockForAlt> alts, GrammarAST labelAST) {
    int decision = ((DecisionState) blkAST.atnState).decision;
    Choice c;
    if (!g.tool.force_atn && AnalysisPipeline.disjoint(g.decisionLOOK.get(decision))) {
        c = getLL1ChoiceBlock(blkAST, alts);
    } else {
        c = getComplexChoiceBlock(blkAST, alts);
    }
    if (labelAST != null) {
        // for x=(...), define x or x_list
        String label = labelAST.getText();
        Decl d = getTokenLabelDecl(label);
        c.label = d;
        getCurrentRuleFunction().addContextDecl(labelAST.getAltLabel(), d);
        if (labelAST.parent.getType() == ANTLRParser.PLUS_ASSIGN) {
            String listLabel = gen.getTarget().getListLabel(label);
            TokenListDecl l = new TokenListDecl(this, listLabel);
            getCurrentRuleFunction().addContextDecl(labelAST.getAltLabel(), l);
        }
    }
    return c;
}

Example 7 with BlockAST

use of org.antlr.v4.tool.ast.BlockAST in project antlr4 by antlr.

the class ParserATNFactory method plus.

/**
	 * From {@code (blk)+} build
	 *
	 * <pre>
	 *   |---------|
	 *   v         |
	 *  [o-blk-o]-&gt;o-&gt;o
	 * </pre>
	 *
	 * We add a decision for loop back node to the existing one at {@code blk}
	 * start.
	 */
@Override
public Handle plus(GrammarAST plusAST, Handle blk) {
    PlusBlockStartState blkStart = (PlusBlockStartState) blk.left;
    BlockEndState blkEnd = (BlockEndState) blk.right;
    preventEpsilonClosureBlocks.add(new Triple<Rule, ATNState, ATNState>(currentRule, blkStart, blkEnd));
    PlusLoopbackState loop = newState(PlusLoopbackState.class, plusAST);
    loop.nonGreedy = !((QuantifierAST) plusAST).isGreedy();
    atn.defineDecisionState(loop);
    LoopEndState end = newState(LoopEndState.class, plusAST);
    blkStart.loopBackState = loop;
    end.loopBackState = loop;
    plusAST.atnState = loop;
    // blk can see loop back
    epsilon(blkEnd, loop);
    BlockAST blkAST = (BlockAST) plusAST.getChild(0);
    if (((QuantifierAST) plusAST).isGreedy()) {
        if (expectNonGreedy(blkAST)) {
            g.tool.errMgr.grammarError(ErrorType.EXPECTED_NON_GREEDY_WILDCARD_BLOCK, g.fileName, plusAST.getToken(), plusAST.getToken().getText());
        }
        // loop back to start
        epsilon(loop, blkStart);
        // or exit
        epsilon(loop, end);
    } else {
        // if not greedy, priority to exit branch; make it first
        // exit
        epsilon(loop, end);
        // loop back to start
        epsilon(loop, blkStart);
    }
    return new Handle(blkStart, end);
}

Example 8 with BlockAST

use of org.antlr.v4.tool.ast.BlockAST in project antlr4 by antlr.

the class ParserATNFactory method makeBlock.

protected Handle makeBlock(BlockStartState start, BlockAST blkAST, List<Handle> alts) {
    BlockEndState end = newState(BlockEndState.class, blkAST);
    start.endState = end;
    for (Handle alt : alts) {
        // hook alts up to decision block
        epsilon(start, alt.left);
        epsilon(alt.right, end);
        // no back link in ATN so must walk entire alt to see if we can
        // strip out the epsilon to 'end' state
        TailEpsilonRemover opt = new TailEpsilonRemover(atn);
        opt.visit(alt.left);
    }
    Handle h = new Handle(start, end);
    //		FASerializer ser = new FASerializer(g, h.left);
    //		System.out.println(blkAST.toStringTree()+":\n"+ser);
    blkAST.atnState = start;
    return h;
}