MacroParser.java

/**
 * Copyright (C) 2013-2016 The Rythm Engine project
 * for LICENSE and other details see:
 * https://github.com/rythmengine/rythmengine
 */
package org.rythmengine.internal.parser.build_in;

import com.stevesoft.pat.Regex;
import org.rythmengine.internal.IContext;
import org.rythmengine.internal.IParser;
import org.rythmengine.internal.Keyword;
import org.rythmengine.internal.Token;
import org.rythmengine.internal.parser.BlockCodeToken;
import org.rythmengine.internal.parser.ParserBase;
import org.rythmengine.utils.S;

/**
 * Define and invoke Macro
 */
public class MacroParser extends KeywordParserFactory {

    @Override
    public Keyword keyword() {
        return Keyword.MACRO;
    }

    public IParser create(final IContext ctx) {
        return new ParserBase(ctx) {
            public Token go() {
                Regex r = reg(dialect());
                if (!r.search(remain())) {
                    raiseParseException("bad @macro statement. Correct usage: @macro(macro-name){...}");
                }
                final String matched = r.stringMatched();
                step(matched.length());
                if (matched.startsWith("\n") || matched.endsWith("\n")) {
                    ctx.getCodeBuilder().addBuilder(new Token.StringToken("\n", ctx));
                    Regex r0 = new Regex("\\n([ \\t\\x0B\\f]*).*");
                    if (r0.search(matched)) {
                        String blank = r0.stringMatched(1);
                        if (blank.length() > 0) {
                            ctx.getCodeBuilder().addBuilder(new Token.StringToken(blank, ctx));
                        }
                    }
                } else {
                    Regex r0 = new Regex("([ \\t\\x0B\\f]*).*");
                    if (r0.search(matched)) {
                        String blank = r0.stringMatched(1);
                        if (blank.length() > 0) {
                            ctx.getCodeBuilder().addBuilder(new Token.StringToken(blank, ctx));
                        }
                    }
                }
                String s = r.stringMatched(1);
                final String macro = S.stripBraceAndQuotation(s);
                return new BlockCodeToken("", ctx()) {
                    @Override
                    public void openBlock() {
                        ctx().getCodeBuilder().pushMacro(macro);
                    }

                    @Override
                    public String closeBlock() {
                        ctx().getCodeBuilder().popMacro();
                        return "";
                    }
                };
            }
        };
    }


    @Override
    protected String patternStr() {
        return "^\\n?[ \\t\\x0B\\f]*%s%s\\s*((?@()))[\\s]*\\{?[ \\t\\x0B\\f]*\\n?";
    }

}