--- /dev/null
+package edu.berkeley.sbp.chr;
+import java.io.*;
+import java.util.*;
+import java.lang.reflect.*;
+import java.lang.ref.*;
+import edu.berkeley.sbp.*;
+import edu.berkeley.sbp.util.*;
+import edu.berkeley.sbp.misc.*;
+import edu.berkeley.sbp.Input.Location;
+
+public class CharAtom extends Atom<Character> {
+
+ public CharAtom(char a) { this(a,a); }
+ public CharAtom(char a, char b) { this(new CharTopology(a, b)); }
+ public CharAtom(CharTopology t) { this.t = t; }
+
+ private CharTopology t;
+ public Topology<Character> top() { return t; }
+
+ public static final char left = (char)9998;
+ public static final char right = (char)9999;
+ public static final Atom leftBrace = new CharAtom(left,left) { public String toString() { return "[{]"; } };
+ public static final Atom rightBrace = new CharAtom(right,right) { public String toString() { return "[}]"; } };
+ public static final Atom braces = new CharAtom(left,right) { public String toString() { return "[{}]"; } };
+
+ public static Atom set(Range.Set r) { return new CharAtom(new CharTopology(r)); }
+
+ public String toString() { return t.toString(); }
+
+ /** returns an element which exactly matches the string given */
+ public static Element string(String s) { return string(s, true); }
+ public static Element string(String s, boolean share) {
+ if (share && s.length() == 0) return epsilon;
+ final String escapified = "\""+StringUtil.escapify(s, "\"\r\n\\")+"\"";
+ Element ret;
+ if (share && s.length() == 1) {
+ ret =
+ new CharAtom(s.charAt(0)) {
+ public String toString() { return escapified; } };
+ } else {
+ Union ret2 = new Union("\""+s+"\"_str", true) {
+ public String toString() { return escapified; } };
+ Element[] refs = new Element[s.length()];
+ for(int i=0; i<refs.length; i++) refs[i] = new CharAtom(s.charAt(i));
+ ret2.add(Sequence.constant(refs, s));
+ ret = ret2;
+ }
+ return ret;
+ }
+
+ private static Union epsilon = new Union("()");
+ static { epsilon.add(Sequence.empty); }
+}