Index: src/OFConstantString.m
==================================================================
--- src/OFConstantString.m
+++ src/OFConstantString.m
@@ -642,6 +642,16 @@
 	if (initialized != SIZE_MAX)
 		[self finishInitialization];
 
 	return [super writeToFile: path];
 }
+
+#ifdef OF_HAVE_BLOCKS
+- (void)enumerateLinesUsingBlock: (of_string_line_enumeration_block_t)block
+{
+	if (initialized != SIZE_MAX)
+		[self finishInitialization];
+
+	return [super enumerateLinesUsingBlock: block];
+}
+#endif
 @end

Index: src/OFString.h
==================================================================
--- src/OFString.h
+++ src/OFString.h
@@ -39,10 +39,14 @@
 	OF_STRING_ENCODING_AUTODETECT = 0xFF
 } of_string_encoding_t;
 
 /* FIXME */
 #define OF_STRING_ENCODING_NATIVE OF_STRING_ENCODING_UTF_8
+
+#ifdef OF_HAVE_BLOCKS
+typedef void (^of_string_line_enumeration_block_t)(OFString *line, BOOL *stop);
+#endif
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 extern int of_string_check_utf8(const char*, size_t, size_t*);
@@ -797,14 +801,23 @@
  * \brief Writes the string into the specified file using UTF-8 encoding.
  *
  * \param path The path of the file to write to
  */
 - (void)writeToFile: (OFString*)path;
+
+#ifdef OF_HAVE_BLOCKS
+/**
+ * Enumerates all lines in the receiver using the specified block.
+ *
+ * \brief block The block to call for each line
+ */
+- (void)enumerateLinesUsingBlock: (of_string_line_enumeration_block_t)block;
+#endif
 @end
 
 #import "OFConstantString.h"
 #import "OFMutableString.h"
 #import "OFString+Hashing.h"
 #import "OFString+Serialization.h"
 #import "OFString+URLEncoding.h"
 #import "OFString+XMLEscaping.h"
 #import "OFString+XMLUnescaping.h"

Index: src/OFString.m
==================================================================
--- src/OFString.m
+++ src/OFString.m
@@ -1925,6 +1925,45 @@
 			       mode: @"wb"];
 	[file writeString: self];
 
 	[pool release];
 }
+
+#ifdef OF_HAVE_BLOCKS
+- (void)enumerateLinesUsingBlock: (of_string_line_enumeration_block_t)block
+{
+	OFAutoreleasePool *pool = [[OFAutoreleasePool alloc] init];
+	const char *cString = s->cString;
+	const char *last = cString;
+	BOOL stop = NO, lastCarriageReturn = NO;
+
+	while (!stop && *cString != 0) {
+		if (lastCarriageReturn && *cString == '\n') {
+			lastCarriageReturn = NO;
+
+			cString++;
+			last++;
+
+			continue;
+		}
+
+		if (*cString == '\n' || *cString == '\r') {
+			block([OFString
+			    stringWithUTF8String: last
+					  length: cString - last], &stop);
+			last = cString + 1;
+
+			[pool releaseObjects];
+		}
+
+		lastCarriageReturn = (*cString == '\r');
+		cString++;
+	}
+
+	if (!stop)
+		block([OFString stringWithUTF8String: last
+					      length: cString - last], &stop);
+
+	[pool release];
+}
+#endif
 @end