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diff --git a/src/com/stevesoft/pat/StrPos.java b/src/com/stevesoft/pat/StrPos.java
new file mode 100755
index 0000000..4a9f287
--- /dev/null
+++ b/src/com/stevesoft/pat/StrPos.java
@@ -0,0 +1,117 @@
+//
+// This software is now distributed according to
+// the Lesser Gnu Public License.  Please see
+// http://www.gnu.org/copyleft/lesser.txt for
+// the details.
+//    -- Happy Computing!
+//
+package com.stevesoft.pat;
+/** 
+        Shareware: package pat
+   <a href="copyright.html">Copyright 2001, Steven R. Brandt</a>
+*/ /**
+StrPos is used internally by regex to parse the regular expression. */
+public class StrPos {
+    String s;
+    int pos;
+    /** Return the position in the string pointed to */
+    public int pos() { return pos; }
+
+    /** This contains the escape character, which is \ by default. */
+    public char esc=Pattern.ESC;
+    char c;
+    /** Returns the current, possibly escaped, character. */
+    public char thisChar() { return c; }
+
+    boolean dontMatch,eos;
+
+    /** tell whether we are at end of string */
+    public boolean eos() { return eos; }
+    /** initialize a StrPos from another StrPos. */
+    public StrPos(StrPos sp) {
+        dup(sp);
+    }
+    /** copy a StrPos from sp to this. */
+    public void dup(StrPos sp) {
+        s = sp.s;
+        pos = sp.pos;
+        c = sp.c;
+        dontMatch = sp.dontMatch;
+        eos = sp.eos;
+    }
+    /** Initialize a StrPos by giving it a String, and a
+         position within the String. */
+    public StrPos(String s,int pos) {
+        this.s=s;
+        this.pos=pos-1;
+        inc();
+    }
+    /** Advance the place where StrPos points within the String.
+         Counts a backslash as part of the next character. */
+    public StrPos inc() {
+        pos++;
+        if(pos >= s.length()) {
+            eos = true;
+            return this;
+        }
+        eos = false;
+        c = s.charAt(pos);
+        if(c == esc && pos+1<s.length()) {
+            pos++;
+            c = s.charAt(pos);
+            if(c != esc)
+                dontMatch = true;
+            else
+                dontMatch = false;
+        } else
+            dontMatch = false;
+        return this;
+    }
+    /** Compare the (possibly escaped) character
+         pointed to by StrPos.  Return true if they are the
+         same, but lways return if character pointed to is escaped. */
+    public boolean match(char ch) {
+        if(dontMatch || eos) return false;
+        return c == ch;
+    }
+    /** As match, but only matches if the character is escaped. */
+    public boolean escMatch(char ch) {
+        if(!dontMatch || eos) return false;
+        return c == ch;
+    }
+
+    /** Returns true if the current
+        character is escaped (preceeded by "\"). */
+    public boolean escaped() { return dontMatch; }
+    /** Increment the string pointer by each character in
+         <pre>st</pre> that matches a non-escaped
+         character. */
+    public boolean incMatch(String st) {
+        StrPos sp = new StrPos(this);
+        int i;
+        for(i=0;i<st.length();i++) {
+            if(!sp.match(st.charAt(i)) )
+                return false;
+            sp.inc();
+        }
+        dup(sp);
+        return true;
+    }
+    /** Read in an integer. */
+    public patInt getPatInt() {
+        patInt pi = null;
+        if(incMatch("inf"))
+            return new patInf();
+        int i,cnt=0;
+        StrPos sp = new StrPos(this);
+        for(i=0;!sp.eos && sp.c >= '0' && sp.c <= '9';i++) {
+            cnt = 10*cnt+sp.c-'0';
+            sp.inc();
+        }
+        if(i==0) return null;
+        dup(sp);
+        return new patInt(cnt);
+    }
+    /** get the string that we are processing. */
+    public String getString() { return s; }
+};