ios - Casting between different UnsafePointer<T> in swift -

i trying use c-api swift. example c-api goes ways:

void dothingsonrawdata(const unsigned char* data);

swift converts to:

void dothingsonrawdata(unsafepointer<uint8>);

now want pass data nsdata function. nsdata.byte returns type:

unsafepointer<()>

struct unsafepointer<t> has constructor

/// convert unsafepointer of different type. /// /// fundamentally unsafe conversion. init<u>(_ from: unsafepointer<u>)

which can use here

dothingsonrawdata(unsafepointer<uint8>(data.bytes))

you can omit generic type because inferred context:

dothingsonrawdata(unsafepointer(data.bytes))

update swift 3: of xcode 8 beta 6, cannot convert directly between different unsafe pointers anymore.

for data: nsdata, data.bytes unsaferawpointer can converted unsafepointer<uint8> assumingmemorybound:

dothingsonrawdata(data.bytes.assumingmemorybound(to: uint8.self))

for data: data simpler:

data.withunsafebytes { dothingsonrawdata($0) }

O9