WithInherit inherits the task hierarchy from inheritFrom into ctx.

Start a new span.

use like this: defer WithSpanFromStackUpdateCtx(&existingCtx)().

Start a new root task or create a child task of an existing task.

create a task and a span within it in one call.

derive task name from call stack (caller's name).

derive task name from call stack (caller's name) and update *ctx to point to be the child task ctx.

create a span during which several child tasks are spawned using the `add` function IMPORTANT FOR USERS: Caller must ensure that the capturing behavior is correct, the Go linter doesn't catch this.

Returned from WithTask or WithSpan.