AddFlat returns the result of appending the flattened value of v to args.
Maps are flattened by appending the alternating keys and map values to args.
Slices are flattened by appending the slice elements to args.
Structs are flattened by appending the alternating names and values of exported fields to args. If v is a nil struct pointer, then nothing is appended. The 'redis' field tag overrides struct field names. See ScanStruct for more information on the use of the 'redis' field tag.
Other types are appended to args as is.