GRXWriter+Immediate.h

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#import "GRXWriter.h"

@interface GRXWriter (Immediate)

// Returns a writer that pulls values from the passed NSEnumerator instance and pushes them to
// its writeable. The NSEnumerator is released when it finishes.
+ (instancetype)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.
+ (instancetype)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.
+ (instancetype)writerWithContainer:(id<NSFastEnumeration>)container;

// Returns a writer that sends the passed value to its writeable and then finishes (releasing the
// value).
+ (instancetype)writerWithValue:(id)value;

// Returns a writer that, as part of its start method, sends the passed error to the writeable
// (then releasing the error).
+ (instancetype)writerWithError:(NSError *)error;

// Returns a writer that, as part of its start method, finishes immediately without sending any
// values to its writeable.
+ (instancetype)emptyWriter;

@end