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apb2006/rex.xq

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call REx from XQuery
Raw
rex.xq
(: ebnf to Java parser for BaseX using REx :)
declare function local:REx-request($ebnf as xs:string,$name as xs:string,$command as xs:string)as item()+{
let $req:=
<request xmlns="http://expath.org/ns/http-client" href='http://www.bottlecaps.de/rex/' method="post">
<multipart media-type="multipart/form-data" boundary="xyzBouNDarYxyz">
<header name="Content-Disposition" value='form-data; name="command"'/>
<body media-type="text/plain"/>
<header name="Content-Disposition" value='form-data; name="input"; filename="{$name}.ebnf"'/>
<body media-type="text/plain"/>
</multipart>
</request>
return http:send-request($req,(),($command,$ebnf))
};
let $ebnf:="S::=INT <?TOKENS?> INT::=[0-9]+"
let $command:="-java -basex -tree"
return local:REx-request($ebnf,"G",$command)[2]
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apb2006 commented May 19, 2016 •
edited 

// This file was generated on Fri May 20, 2016 14:14 (UTC+02) by REx v5.39 which is Copyright (c) 1979-2016 by Gunther Rademacher <grd@gmx.net>
// REx command line: G.ebnf -java -basex -tree

import java.io.IOException;
import java.util.Arrays;

import org.basex.build.MemBuilder;
import org.basex.build.SingleParser;
import org.basex.core.MainOptions;
import org.basex.io.IOContent;
import org.basex.query.value.item.Str;
import org.basex.query.value.node.ANode;
import org.basex.query.value.node.DBNode;
import org.basex.util.Atts;
import org.basex.util.Token;

public class G
{
  public static class ParseException extends RuntimeException
  {
    private static final long serialVersionUID = 1L;
    private int begin, end, offending, expected, state;

    public ParseException(int b, int e, int s, int o, int x)
    {
      begin = b;
      end = e;
      state = s;
      offending = o;
      expected = x;
    }

    @Override
    public String getMessage()
    {
      return offending < 0 ? "lexical analysis failed" : "syntax error";
    }

    public int getBegin() {return begin;}
    public int getEnd() {return end;}
    public int getState() {return state;}
    public int getOffending() {return offending;}
    public int getExpected() {return expected;}
  }

  public interface EventHandler
  {
    public void reset(CharSequence string);
    public void startNonterminal(String name, int begin);
    public void endNonterminal(String name, int end);
    public void terminal(String name, int begin, int end);
    public void whitespace(int begin, int end);
  }

  public static class TopDownTreeBuilder implements EventHandler
  {
    private CharSequence input = null;
    private Nonterminal[] stack = new Nonterminal[64];
    private int top = -1;

    @Override
    public void reset(CharSequence input)
    {
      this.input = input;
      top = -1;
    }

    @Override
    public void startNonterminal(String name, int begin)
    {
      Nonterminal nonterminal = new Nonterminal(name, begin, begin, new Symbol[0]);
      if (top >= 0) addChild(nonterminal);
      if (++top >= stack.length) stack = Arrays.copyOf(stack, stack.length << 1);
      stack[top] = nonterminal;
    }

    @Override
    public void endNonterminal(String name, int end)
    {
      stack[top].end = end;
      if (top > 0) --top;
    }

    @Override
    public void terminal(String name, int begin, int end)
    {
      addChild(new Terminal(name, begin, end));
    }

    @Override
    public void whitespace(int begin, int end)
    {
    }

    private void addChild(Symbol s)
    {
      Nonterminal current = stack[top];
      current.children = Arrays.copyOf(current.children, current.children.length + 1);
      current.children[current.children.length - 1] = s;
    }

    public void serialize(EventHandler e)
    {
      e.reset(input);
      stack[0].send(e);
    }
  }

  public static abstract class Symbol
  {
    public String name;
    public int begin;
    public int end;

    protected Symbol(String name, int begin, int end)
    {
      this.name = name;
      this.begin = begin;
      this.end = end;
    }

    public abstract void send(EventHandler e);
  }

  public static class Terminal extends Symbol
  {
    public Terminal(String name, int begin, int end)
    {
      super(name, begin, end);
    }

    @Override
    public void send(EventHandler e)
    {
      e.terminal(name, begin, end);
    }
  }

  public static class Nonterminal extends Symbol
  {
    public Symbol[] children;

    public Nonterminal(String name, int begin, int end, Symbol[] children)
    {
      super(name, begin, end);
      this.children = children;
    }

    @Override
    public void send(EventHandler e)
    {
      e.startNonterminal(name, begin);
      int pos = begin;
      for (Symbol c : children)
      {
        if (pos < c.begin) e.whitespace(pos, c.begin);
        c.send(e);
        pos = c.end;
      }
      if (pos < end) e.whitespace(pos, end);
      e.endNonterminal(name, end);
    }
  }

  public static ANode parseS(Str str) throws IOException
  {
    BaseXFunction baseXFunction = new BaseXFunction()
    {
      @Override
      public void execute(G p) {p.parse_S();}
    };
    return baseXFunction.call(str);
  }

  public static abstract class BaseXFunction
  {
    protected abstract void execute(G p);

    public ANode call(Str str) throws IOException
    {
      String input = str.toJava();
      SingleParser singleParser = new SingleParser(new IOContent(""), MainOptions.get())
      {
        @Override
        protected void parse() throws IOException {}
      };
      MemBuilder memBuilder = new MemBuilder(input, singleParser);
      memBuilder.init();
      BaseXTreeBuilder treeBuilder = new BaseXTreeBuilder(memBuilder);
      G parser = new G();
      parser.initialize(input, treeBuilder);
      try
      {
        execute(parser);
      }
      catch (ParseException pe)
      {
        memBuilder = new MemBuilder(input, singleParser);
        memBuilder.init();
        Atts atts = new Atts();
        atts.add(Token.token("b"), Token.token(pe.getBegin() + 1));
        atts.add(Token.token("e"), Token.token(pe.getEnd() + 1));
        if (pe.getOffending() < 0)
        {
          atts.add(Token.token("s"), Token.token(pe.getState()));
        }
        else
        {
          atts.add(Token.token("o"), Token.token(pe.getOffending()));
          atts.add(Token.token("x"), Token.token(pe.getExpected()));
        }
        memBuilder.openElem(Token.token("ERROR"), atts, new Atts());
        memBuilder.text(Token.token(parser.getErrorMessage(pe)));
        memBuilder.closeElem();
      }
      return new DBNode(memBuilder.data());
    }
  }

  public static class BaseXTreeBuilder implements EventHandler
  {
    private CharSequence input;
    private MemBuilder builder;
    private Atts nsp = new Atts();
    private Atts atts = new Atts();

    public BaseXTreeBuilder(MemBuilder b)
    {
      input = null;
      builder = b;
    }

    @Override
    public void reset(CharSequence string)
    {
      input = string;
    }

    @Override
    public void startNonterminal(String name, int begin)
    {
      try
      {
        builder.openElem(Token.token(name), atts, nsp);
      }
      catch (IOException e)
      {
        throw new RuntimeException(e);
      }
    }

    @Override
    public void endNonterminal(String name, int end)
    {
      try
      {
        builder.closeElem();
      }
      catch (IOException e)
      {
        throw new RuntimeException(e);
      }
    }

    @Override
    public void terminal(String name, int begin, int end)
    {
      if (name.charAt(0) == '\'')
      {
        name = "TOKEN";
      }
      startNonterminal(name, begin);
      characters(begin, end);
      endNonterminal(name, end);
    }

    @Override
    public void whitespace(int begin, int end)
    {
      characters(begin, end);
    }

    private void characters(int begin, int end)
    {
      if (begin < end)
      {
        try
        {
          builder.text(Token.token(input.subSequence(begin, end).toString()));
        }
        catch (IOException e)
        {
          throw new RuntimeException(e);
        }
      }
    }
  }

  public G()
  {
  }

  public G(CharSequence string, EventHandler t)
  {
    initialize(string, t);
  }

  public void initialize(CharSequence string, EventHandler eh)
  {
    eventHandler = eh;
    input = string;
    size = input.length();
    reset(0, 0, 0);
  }

  public CharSequence getInput()
  {
    return input;
  }

  public int getTokenOffset()
  {
    return b0;
  }

  public int getTokenEnd()
  {
    return e0;
  }

  public final void reset(int l, int b, int e)
  {
            b0 = b; e0 = b;
    l1 = l; b1 = b; e1 = e;
    end = e;
    eventHandler.reset(input);
  }

  public void reset()
  {
    reset(0, 0, 0);
  }

  public static String getOffendingToken(ParseException e)
  {
    return e.getOffending() < 0 ? null : TOKEN[e.getOffending()];
  }

  public static String[] getExpectedTokenSet(ParseException e)
  {
    String[] expected;
    if (e.getExpected() < 0)
    {
      expected = getTokenSet(- e.getState());
    }
    else
    {
      expected = new String[]{TOKEN[e.getExpected()]};
    }
    return expected;
  }

  public String getErrorMessage(ParseException e)
  {
    String[] tokenSet = getExpectedTokenSet(e);
    String found = getOffendingToken(e);
    String prefix = input.subSequence(0, e.getBegin()).toString();
    int line = prefix.replaceAll("[^\n]", "").length() + 1;
    int column = prefix.length() - prefix.lastIndexOf('\n');
    int size = e.getEnd() - e.getBegin();
    return e.getMessage()
         + (found == null ? "" : ", found " + found)
         + "\nwhile expecting "
         + (tokenSet.length == 1 ? tokenSet[0] : java.util.Arrays.toString(tokenSet))
         + "\n"
         + (size == 0 || found != null ? "" : "after successfully scanning " + size + " characters beginning ")
         + "at line " + line + ", column " + column + ":\n..."
         + input.subSequence(e.getBegin(), Math.min(input.length(), e.getBegin() + 64))
         + "...";
  }

  public void parse_S()
  {
    eventHandler.startNonterminal("S", e0);
    lookahead1(0);                  // INT
    consume(1);                     // INT
    eventHandler.endNonterminal("S", e0);
  }

  private void consume(int t)
  {
    if (l1 == t)
    {
      eventHandler.terminal(TOKEN[l1], b1, e1);
      b0 = b1; e0 = e1; l1 = 0;
    }
    else
    {
      error(b1, e1, 0, l1, t);
    }
  }

  private void lookahead1(int set)
  {
    if (l1 == 0)
    {
      l1 = match(set);
      b1 = begin;
      e1 = end;
    }
  }

  private int error(int b, int e, int s, int l, int t)
  {
    throw new ParseException(b, e, s, l, t);
  }

  private int     b0, e0;
  private int l1, b1, e1;
  private EventHandler eventHandler = null;
  private CharSequence input = null;
  private int size = 0;
  private int begin = 0;
  private int end = 0;

  private int match(int tokenSetId)
  {
    begin = end;
    int current = end;
    int result = INITIAL[tokenSetId];
    int state = 0;

    for (int code = result & 1; code != 0; )
    {
      int charclass;
      int c0 = current < size ? input.charAt(current) : 0;
      ++current;
      if (c0 < 0x80)
      {
        charclass = MAP0[c0];
      }
      else if (c0 < 0xd800)
      {
        int c1 = c0 >> 5;
        charclass = MAP1[(c0 & 31) + MAP1[(c1 & 31) + MAP1[c1 >> 5]]];
      }
      else
      {
        charclass = 0;
      }

      state = code;
      int i0 = (charclass << 1) + code - 1;
      code = TRANSITION[i0];

      if (code > 1)
      {
        result = code;
        code &= 1;
        end = current;
      }
    }

    result >>= 1;
    if (result == 0)
    {
      end = current - 1;
      int c1 = end < size ? input.charAt(end) : 0;
      if (c1 >= 0xdc00 && c1 < 0xe000)
      {
        --end;
      }
      return error(begin, end, state, -1, -1);
    }

    if (end > size) end = size;
    return (result & 3) - 1;
  }

  private static String[] getTokenSet(int tokenSetId)
  {
    java.util.ArrayList<String> expected = new java.util.ArrayList<>();
    int s = tokenSetId < 0 ? - tokenSetId : INITIAL[tokenSetId] & 1;
    for (int i = 0; i < 2; i += 32)
    {
      int j = i;
      int i0 = (i >> 5) * 1 + s - 1;
      int f = EXPECTED[i0];
      for ( ; f != 0; f >>>= 1, ++j)
      {
        if ((f & 1) != 0)
        {
          expected.add(TOKEN[j]);
        }
      }
    }
    return expected.toArray(new String[]{});
  }

  private static final int[] MAP0 =
  {
    /*   0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*  35 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /*  70 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 105 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  };

  private static final int[] MAP1 =
  {
    /*   0 */ 54, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
    /*  26 */ 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56,
    /*  52 */ 56, 56, 88, 104, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 88,
    /*  78 */ 88, 88, 88, 88, 88, 88, 88, 88, 88, 88, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 110 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0
  };

  private static final int[] INITIAL =
  {
    /* 0 */ 1
  };

  private static final int[] TRANSITION =
  {
    /* 0 */ 0, 0, 5, 0
  };

  private static final int[] EXPECTED =
  {
    /* 0 */ 2
  };

  private static final String[] TOKEN =
  {
    "(0)",
    "INT"
  };
}

// End

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