Cannot use inflight functions that take preflight class objects as parameters

[Chriscbr]

Use Case

Currently it's not possible to write use functions that take preflight class objects as parameters, since accessing any fields or calling any methods on the object will result in a compilation error:

bring cloud;

let removePrefix = inflight (
  bucket: cloud.Bucket,
  prefix: str
) => {
  for key in bucket.list(prefix) {
    bucket.delete(key);
  }
};

As of writing the following errors are raised:

error: Expression of type "Bucket" references an unknown preflight object, can't qualify its capabilities
  --> wing/main.w:7:14
  |
7 |   for key in bucket.list(prefix) {
  |              ^^^^^^
  |
  = hint: Use a `lift` block to explicitly qualify the preflight object and disable this error
  = hint: For details see: https://www.winglang.io/docs/concepts/inflights#explicit-lift-qualification


error: Expression of type "Bucket" references an unknown preflight object, can't qualify its capabilities
  --> wing/main.w:8:5
  |
8 |     bucket.delete(key);
  |     ^^^^^^
  |
  = hint: Use a `lift` block to explicitly qualify the preflight object and disable this error
  = hint: For details see: https://www.winglang.io/docs/concepts/inflights#explicit-lift-qualification

The reason for these errors is that the lifting system used to automatically generate permissions does not track or calculate enough information to support these types of examples.

Related to #76

Proposed Solution

No response

Implementation Notes

No response

Component

Compiler

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