added Unicode escape patch from Toralf Wittner

2 files changed, 95 insertions, 1 deletions

diff --git a/src/jvm/clojure/lang/LispReader.java b/src/jvm/clojure/lang/LispReader.java
index 6fda4c9e..ed73d75f 100644
--- a/src/jvm/clojure/lang/LispReader.java
+++ b/src/jvm/clojure/lang/LispReader.java
@@ -198,6 +198,42 @@ static private Object readNumber(PushbackReader r, char initch) throws Exception
 	return n;

 }

 

+static private int readUnicodeChar(String token, int offset, int length, int base) throws Exception {

+    if (token.length() != offset + length)

+        throw new IllegalArgumentException("Invalid unicode character: \\" + token);

+    int uc = 0;

+    for (int i = offset; i < offset + length; ++i)

+        {

+        int d = Character.digit(token.charAt(i), base);

+        if (d == -1)

+            throw new IllegalArgumentException("Invalid digit: " + (char) d);

+        uc = uc * base + d;

+        }

+    return (char) uc;

+}

+

+static private int readUnicodeChar(PushbackReader r, int initch, int base, int length, boolean exact) throws Exception {

+    int uc = Character.digit(initch, base);

+    if(uc == -1)

+        throw new IllegalArgumentException("Invalid digit: " + initch);

+    int i = 1;

+    for(; i < length; ++i)

+        {

+        int ch = r.read();

+        if(ch == -1 || isWhitespace(ch) || isMacro(ch))

+            {

+            unread(r, ch);

+            break;

+            }

+        int d = Character.digit(ch, base);

+        if(d == -1)

+            throw new IllegalArgumentException("Invalid digit: " + (char) ch);

+        uc = uc * base + d;

+        }

+    if(i != length && exact)

+        throw new IllegalArgumentException("Invalid character length: " + i + ", should be: " + length);

+    return uc;

+}

 

 static private Object interpretToken(String s) throws Exception{

 	if(s.equals("nil"))

@@ -311,8 +347,32 @@ static class StringReader extends AFn{
 						break;

 					case '"':

 						break;

+					case 'b':

+					    ch = '\b';

+					    break;

+                    case 'f':

+                        ch = '\f';

+                        break;

+                    case 'u':

+                        {

+                        ch = r.read();

+                        if (Character.isDigit(ch))

+                            ch = readUnicodeChar((PushbackReader) r, ch, 16, 4, true);

+                        else

+                            throw new Exception("Invalid unicode escape: \\" + (char) ch);

+                        break;

+                        }

 					default:

-						throw new Exception("Unsupported escape character: \\" + (char) ch);

+					    {

+					    if (Character.isDigit(ch))

+					        {

+					        ch = readUnicodeChar((PushbackReader) r, ch, 8, 3, false);

+					        if (ch > 0377)

+					            throw new Exception("Octal escape sequence must be in range [0, 377].");

+					        }

+					    else

+					        throw new Exception("Unsupported escape character: \\" + (char) ch);    

+					    }

 					}

 				}

 			sb.append((char) ch);

@@ -653,6 +713,22 @@ static class CharacterReader extends AFn{
 			return ' ';

 		else if(token.equals("tab"))

 			return '\t';

+        else if(token.equals("backspace"))

+            return '\b';

+        else if(token.equals("formfeed"))

+            return '\f';

+        else if (token.startsWith("u"))

+            return (char) readUnicodeChar(token, 1, 4, 16);

+        else if (token.startsWith("o"))

+            {

+            int len = token.length() - 1;

+            if (len > 3)

+                throw new Exception("Invalid octal escape sequence length: " + len);

+            int uc = readUnicodeChar(token, 1, len, 8);

+            if (uc > 0377)

+                throw new Exception("Octal escape sequence must be in range [0, 377].");

+            return (char) uc;

+            }

 		throw new Exception("Unsupported character: \\" + token);

 	}

 

diff --git a/src/jvm/clojure/lang/RT.java b/src/jvm/clojure/lang/RT.java
index 02858459..4d3b60dd 100644
--- a/src/jvm/clojure/lang/RT.java
+++ b/src/jvm/clojure/lang/RT.java
@@ -902,6 +902,12 @@ static public void print(Object x, Writer w) throws Exception{
 					case '\\':
 						w.write("\\\\");
 						break;
+					case '\f':
+					    w.write("\\f");
+					    break;
+                    case '\b':
+                        w.write("\\b");
+                        break;
 					default:
 						w.write(c);
 					}
@@ -981,6 +987,12 @@ static public void print(Object x, Writer w) throws Exception{
 				case ' ':
 					w.write("space");
 					break;
+	            case '\b':
+	                w.write("backspace");
+	                break;
+	            case '\f':
+	                w.write("formfeed");
+	                break;
 				default:
 					w.write(c);
 				}
@@ -1034,6 +1046,12 @@ static public void formatStandard(Writer w, Object obj) throws IOException{
 			case ' ':
 				w.write("space");
 				break;
+            case '\b':
+                w.write("backspace");
+                break;
+            case '\f':
+                w.write("formfeed");
+                break;
 			default:
 				w.write(c);
 			}