[swift] Update tutorial for getRootAs -> getCheckedRoot

[peeeeter]

WRT #7738, the tutorial still gives

// create a ByteBuffer(:) from an [UInt8] or Data()
let buf = // Get your data
 
// Get an accessor to the root object inside the buffer.
let monster = Monster.getRootAsMonster(bb: ByteBuffer(bytes: buf))

[mustiikhalil]

Hey,

Thanks for opening this issue! If you want to try to update the docs, feel free to open a PR for this.

[oxygen]

Sorry to bother you on an unrelated bug,

but flatc generates getRootAs* methods in Swift for you?

It doesn't for me (C# and Java are generated).

Is there something I am missing or not doing? I am doing root_type SomeTable;

[mustiikhalil]

@oxygen so the generated getRootAs* methods are deprecated within swift. the new way is described below. Or you can follow the DocC documentation within xcode

let monster: Monster = try getCheckedRoot(.....)

flatbuffers/swift/Sources/FlatBuffers/Documentation.docc/Resources/code/swift/swift_code_12.swift

Line 9 in 99fda81

let monster: Monster = try! getCheckedRoot(byteBuffer: &byteBuffer)

[oxygen]

@mustiikhalil Thank you, this was not intuitive and I was about to compute the offset which would have been ugly. Hopefully the getRootAs functions will be undeprecated and modified into throwing from this checked thing (perhaps on the next major version).

This would save you from updating the tutorial, so we’re now relevant to this thread :)

[mustiikhalil]

Maybe we can add a helper function through the generator, but it will run through this function.

[oxygen]

@mustiikhalil I didn't look yet but I supose getCheckedRoot will throw instead of crashing the program with a fatal error on malformed data. So yeah