Imports code of the RX library.
diff --git a/src/objective-c/RxLibrary/GRXImmediateWriter.h b/src/objective-c/RxLibrary/GRXImmediateWriter.h
new file mode 100644
index 0000000..568dbe6
--- /dev/null
+++ b/src/objective-c/RxLibrary/GRXImmediateWriter.h
@@ -0,0 +1,40 @@
+#import <Foundation/Foundation.h>
+
+#import "GRXWriter.h"
+
+// Utility to construct GRXWriter instances from values that are immediately available when
+// required. The returned writers all support pausing and early termination.
+//
+// Unless the writeable callback pauses them or stops them early, these writers will do all their
+// interactions with the writeable before the start method returns.
+@interface GRXImmediateWriter : NSObject<GRXWriter>
+
+// Returns a writer that pulls values from the passed NSEnumerator instance and pushes them to
+// its writeable. The NSEnumerator is released when it finishes.
++ (id<GRXWriter>)writerWithEnumerator:(NSEnumerator *)enumerator;
+
+// Returns a writer that pushes to its writeable the successive values returned by the passed
+// block. When the block first returns nil, it is released.
++ (id<GRXWriter>)writerWithValueSupplier:(id (^)())block;
+
+// Returns a writer that iterates over the values of the passed container and pushes them to
+// its writeable. The container is released when the iteration is over.
+//
+// Note that the usual speed gain of NSFastEnumeration over NSEnumerator results from not having to
+// call one method per element. Because GRXWriteable instances accept values one by one, that speed
+// gain doesn't happen here.
++ (id<GRXWriter>)writerWithContainer:(id<NSFastEnumeration>)container;
+
+// Returns a writer that sends the passed value to its writeable and then finishes (releasing the
+// value).
++ (id<GRXWriter>)writerWithValue:(id)value;
+
+// Returns a writer that, as part of its start method, sends the passed error to the writeable
+// (then releasing the error).
++ (id<GRXWriter>)writerWithError:(NSError *)error;
+
+// Returns a writer that, as part of its start method, finishes immediately without sending any
+// values to its writeable.
++ (id<GRXWriter>)emptyWriter;
+
+@end