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diff --git a/src/compiler/scala/tools/util/Position.java b/src/compiler/scala/tools/util/Position.java
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+++ b/src/compiler/scala/tools/util/Position.java
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+/*     ____ ____  ____ ____  ______                                     *\
+**    / __// __ \/ __// __ \/ ____/    SOcos COmpiles Scala             **
+**  __\_ \/ /_/ / /__/ /_/ /\_ \       (c) 2002, LAMP/EPFL              **
+** /_____/\____/\___/\____/____/                                        **
+\*                                                                      */
+
+// $Id$
+
+package scala.tools.util;
+
+/**
+ * This class represents a position in a source file. Such a position
+ * is defined by a source file (mandatory), a line number (optional)
+ * and a column number (optional, may be specified only if the line
+ * number is defined).
+ *
+ * Line (Column) numbers range from 0 to Integer.MAX_VALUE. A value of
+ * 0 indicates that the line (column) is undefined, 1 represents the
+ * first line (column). Negative values are prohibited.
+ *
+ * The class provides also functions to encode a line number and a
+ * column number into one single integer. The encode line (column)
+ * numbers range from 0 to LINE_MASK (COLUMN_MASK), where 0 indicates
+ * that the line (column) is the undefined and 1 represents the first
+ * line (column). Line (Column) numbers greater than LINE_MASK
+ * (COLUMN_MASK) are replaced by LINE_MASK (COLUMN_MASK). Furthermore,
+ * if the encoded line number is LINE_MASK, the column number is
+ * always set to 0.
+ *
+ * The following properties hold:
+ * - the undefined position is 0: encode(0,0) == 0
+ * - encodings are non-negative : encode(line,column) >= 0
+ * - position order is preserved:
+ *   (line1 < line2) || (line1 == line2 && column1 < column2)
+ * implies
+ *   encode(line1,column1) <= encode(line2,column2)
+ */
+public class Position {
+
+    //########################################################################
+    // Public Constants
+
+    /** Number of bits used to encode the line number */
+    public static final int LINE_BITS   = 20;
+    /** Number of bits used to encode the column number */
+    public static final int COLUMN_BITS = 31 - LINE_BITS; // no negatives => 31
+
+    /** Mask to decode the line number */
+    public static final int LINE_MASK   = (1 << LINE_BITS) - 1;
+    /** Mask to decode the column number */
+    public static final int COLUMN_MASK = (1 << COLUMN_BITS) - 1;
+
+    /** The undefined position */
+    public static final int NOPOS       = 0;
+
+    /** The first position in a source file */
+    public static final int FIRSTPOS    = encode(1, 1);
+
+    //########################################################################
+    // Public Functions
+
+    /** Encodes a position into a single integer. */
+    public static int encode(int line, int column) {
+        assert line >= 0 : line;
+        assert line == 0 ? column == 0 : column >= 0 : line + "," + column;
+        if (line >= LINE_MASK) { line = LINE_MASK; column = 0; }
+        if (column > COLUMN_MASK) column = COLUMN_MASK;
+        return (line << COLUMN_BITS) | column;
+    }
+
+    /** Returns the line number of the encoded position. */
+    public static int line(int position) {
+        return (position >> COLUMN_BITS) & LINE_MASK;
+    }
+
+    /** Returns the column number of the encoded position. */
+    public static int column(int position) {
+        return position & COLUMN_MASK;
+    }
+
+    /** Returns a string representation of the encoded position. */
+    public static String toString(int position) {
+        return line(position) + ":" + column(position);
+    }
+
+    //########################################################################
+    // Private Fields
+
+    /** The position's source file */
+    private final SourceFile source;
+
+    /** The position's line number */
+    private final int line;
+
+    /** The position's column number */
+    private final int column;
+
+    //########################################################################
+    // Public Constructors
+
+    /** Initializes a new instance. */
+    public Position(String sourcename) {
+        this(new SourceFile(sourcename, new char[0]));
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile source) {
+        this(source, 0, 0);
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile source, int position) {
+        this(source, line(position), column(position));
+    }
+
+    /** Initializes a new instance. */
+    public Position(SourceFile source, int line, int column) {
+        this.source = source;
+        this.line = line;
+        this.column = column;
+        assert source != null;
+        assert line >= 0 : line;
+        assert line == 0 ? column == 0 : column >= 0 : line + "," + column;
+    }
+
+    //########################################################################
+    // Public Methods
+
+    /** Returns the underlying abstract file's name. */
+    public String getName() {
+        return source.getFile().getName();
+    }
+
+    /** Returns the underlying abstract file's path position. */
+    public String getPath() {
+        return source.getFile().getPath();
+    }
+
+    /** Returns the underlying abstract file. */
+    public AbstractFile getAbstractFile() {
+        return source.getFile();
+    }
+
+    /** Returns the source file. */
+    public SourceFile getSourceFile() {
+        return source;
+    }
+
+    /** Returns the line content or null if it's unavailable. */
+    public String getLineContent() {
+        return line == 0 ? null : source.getLine(line);
+    }
+
+    /** Returns the line number. */
+    public int getLineNumber() {
+        return line;
+    }
+
+    /** Returns the column number. */
+    public int getColumnNumber() {
+        return column;
+    }
+
+    /** Returns the line and column numbers encoded in an int. */
+    public int getLineAndColumnNumber() {
+        return encode(line, column);
+    }
+
+    /** Returns a string representation of this position. */
+    public String toString() {
+        StringBuffer buffer = new StringBuffer(source.getFile().getPath());
+        if (line > 0) buffer.append(":").append(line);
+        if (line > 0 && column > 0) buffer.append(":").append(column);
+        return buffer.toString();
+    }
+
+    /** Returns the hash code of this position. */
+    public int hashCode() {
+        return source.hashCode() ^ getLineAndColumnNumber();
+    }
+
+    /** Returns true iff the given object represents the same position. */
+    public boolean equals(Object object) {
+        if (!(object instanceof Position)) return false;
+        Position that = (Position)object;
+        return this.source == that.source
+            && this.line == that.line
+            && this.column == that.column;
+    }
+
+    //########################################################################
+}