lobster.transforms.Lambda doesn't work properly

[karinazad]

lobster.transforms.Lambda seems broken

1. needs to implement _check_inputs
2. even with that implemented, it doesn't work properly on tuples. In the example below it gives an explicit error but in other cases, fails silently. I think the issue is with the implementation of Transform itself

---

Example:

Compare torchvision.transforms.Lambda which gives the expected output

from torchvision.transforms import Lambda

transform = Lambda(lambda item: (item[0] + 1, item[1]))

transform((1, 1))

>>> (2, 1)

and lobster.transforms.Lambda

from lobster.transforms import Lambda

transform = Lambda(lambda item: (item[0] + 1, item[1]))

transform((1, 1))

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[31], line 5
      1 from lobster.transforms import Lambda
      3 transform = Lambda(lambda item: (item[0] + 1, item[1]))
----> 5 transform((1, 1))

File ~/Desktop/code/lobster/.venv/lib/python3.10/site-packages/torch/nn/modules/module.py:1736, in Module._wrapped_call_impl(self, *args, **kwargs)
   1734     return self._compiled_call_impl(*args, **kwargs)  # type: ignore[misc]
   1735 else:
-> 1736     return self._call_impl(*args, **kwargs)

File ~/Desktop/code/lobster/.venv/lib/python3.10/site-packages/torch/nn/modules/module.py:1747, in Module._call_impl(self, *args, **kwargs)
   1742 # If we don't have any hooks, we want to skip the rest of the logic in
   1743 # this function, and just call forward.
   1744 if not (self._backward_hooks or self._backward_pre_hooks or self._forward_hooks or self._forward_pre_hooks
   1745         or _global_backward_pre_hooks or _global_backward_hooks
   1746         or _global_forward_hooks or _global_forward_pre_hooks):
-> 1747     return forward_call(*args, **kwargs)
   1749 result = None
   1750 called_always_called_hooks = set()

File ~/Desktop/code/lobster/src/lobster/transforms/_transform.py:105, in Transform.forward(self, *inputs)
    103 for x, transformable in zip(flattened, transformables):
    104     if transformable:
--> 105         y = self._transform(x, inputs)
    106     else:
    107         y = x

File ~/Desktop/code/lobster/src/lobster/transforms/_lambda.py:46, in Lambda._transform(self, input, parameters)
     29 """
     30 Parameters
     31 ----------
   (...)
     43 
     44 """
     45 if isinstance(input, self._types):
---> 46     return self._fn(input)
     47 else:
     48     return input

Cell In[31], line 3
      1 from lobster.transforms import Lambda
----> 3 transform = Lambda(lambda item: (item[0] + 1, item[1]))
      5 transform((1, 1))

TypeError: 'int' object is not subscriptable