# Enter in a statement block `node` as inside a new scope.
	# The block can be optionally attached to an `escapemark`.
	fun enter_visit_block(node: nullable AExpr, escapemark: nullable EscapeMark)
	do
		if node == null then return
		var scope = new Scope
		scope.escapemark = escapemark
		scopes.unshift(scope)
		enter_visit(node)
		shift_scope
	end