@interface Foundation.__NSSwiftData : NSData { void /* unknown type, empty encoding */ _backing; void /* unknown type, empty encoding */ _range; } @property (nonatomic, readonly) long long length; @property (nonatomic, readonly) void *bytes; - (BOOL)_isCompact; - (BOOL)_providesConcreteBacking; - (id)initWithBytesNoCopy:(void *)a0 length:(long long)a1; - (id)init; - (id)initWithContentsOfURL:(id)a0 options:(unsigned long long)a1 error:(id *)a2; - (id)initWithBytesNoCopy:(void *)a0 length:(long long)a1 freeWhenDone:(BOOL)a2; - (id)initWithContentsOfMappedFile:(id)a0 error:(id *)a1; - (id)initWithContentsOfFile:(id)a0; - (id)initWithContentsOfURL:(id)a0; - (id)initWithBase64EncodedString:(id)a0 options:(unsigned long long)a1; - (id)initWithContentsOfFile:(id)a0 options:(unsigned long long)a1 error:(id *)a2; - (id)initWithBytes:(void *)a0 length:(long long)a1; - (id)initWithBytesNoCopy:(void *)a0 length:(long long)a1 deallocator:(id /* block */)a2; - (id)initWithData:(id)a0; - (id)initWithContentsOfFile:(id)a0 error:(id *)a1; - (id)initWithContentsOfMappedFile:(id)a0; - (void).cxx_destruct; - (id)initWithBase64EncodedData:(id)a0 options:(unsigned long long)a1; - (id)mutableCopyWithZone:(void *)a0; - (id)initWithCoder:(id)a0; - (id)copyWithZone:(void *)a0; @end