start Replaceable Group
Inserts a "Replaceable Group" starting marker in the slot table at the current execution position. A Replaceable Group is a group which cannot be moved between its siblings, but can be removed or inserted. These groups are inserted by the compiler around branches of conditional logic in Composable functions such as if expressions, when expressions, early returns, and null-coalescing operators.
A call to startReplaceableGroup must be matched with a corresponding call to endReplaceableGroup.
Warning: This is expected to be executed by the compiler only and should not be called directly from source code. Call this API at your own risk.
See also
Parameters
key
The source-location-based key for the group. Expected to be unique among its siblings.