checkpoint

[sbp.git] / src / edu / berkeley / sbp / Input.java

diff --git a/src/edu/berkeley/sbp/Input.java b/src/edu/berkeley/sbp/Input.java
index 846fd9a..d19b208 100644 (file)
--- a/src/edu/berkeley/sbp/Input.java
+++ b/src/edu/berkeley/sbp/Input.java
@@ -6,7 +6,7 @@ import java.lang.ref.*;
 import edu.berkeley.sbp.*;
 import edu.berkeley.sbp.util.*;
 
-/** a stream of tokens to be parsed */
+/** <font color=purple>a stream of <tt>Token</tt>s to be parsed</font> */
 public interface Input<Token> {
 
     /** returns the token just beyond the current location and advances beyond it */
@@ -15,23 +15,19 @@ public interface Input<Token> {
     /** returns the location the input stream is currently at */
     public Location<Token> getLocation();
 
-    /** a location <i>between tokens<i> in the input stream */
-    public static interface Location<Tok> extends Comparable<Location> {
+    /** <font color=purple>a location (position) in the input stream -- <i>between tokens</i></font> */
+    public static interface Location<Token> extends Comparable<Location> {
+
+        /** return the region between this location and <tt>loc</tt> */
+        public Region<Token> createRegion(Location<Token> loc);
+
         public String toString();
     }
 
-    public static class Region<Loc extends Location> /* implements Topology<Location<Tok>> */ {
-        public final Loc start;
-        public final Loc end;
-        public Region(Loc a, Loc b) {
-            switch(a.compareTo(b)) {
-                case -1:
-                case  0: start=a; end=b; return;
-                case  1: start=b; end=a; return;
-                default: throw new Error("impossible");
-            }
-        }
+    /** <font color=purple>a contiguous set of <tt>Location</tt>s</font> */
+    public static interface Region<Token> /* implements Topology<Location<Tok>> */ {
     }
+
 }