Logic extracting for different sprites

[nighca]

To improve code reuse, we need a mechanism for extracting common logic from sprites. This becomes challenging when the shared logic relies on a sprite's specific fields or methods.

For instance:

A.spx

var (
  count int
)

func increase() {
  count++
}

B.spx

var (
  count int
)

func increase() {
  count++
}

Currently, there's no good way to extract logic dependent on the count field or increase method for A & B.

[nighca]

We may use a standalone (invisible) sprite to extract common logic & use embedding to share it:

Common.spx:

var (
  count int
)

func increase() {
  count++
}

A.spx / B.spx:

var (
  Common
)

onStart => {
  increase()
}