iPhone - encoding and decoding a NSValue

So I read here on SO that I can encode a CGLayerRef to a NSValue using

NSValue *myCopy = [[NSValue all开发者_C百科oc] initWithBytes:&myLayer objCType:@encode(CGLayerRef)]; 

but how do I recreate the CGLayerRef from myCopy?

thanks

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This should work:

CGLayerRef giveMeBackTheLayer;
[myCopy getValue:&giveMeBackTheLayer];