1. An apparatus, comprising: a memory configured to store information defining multiple function block types; a function block editor configured to dynamically create or modify one or more of the function block types using input received through a graphical user interface, wherein the function block editor is configured to (i) define one or more parameters for a function block type being created or modified, (ii) create one or more new parameters for the function block type being created or modified, (iii) define and modify a form layout for the function block type being created or modified, and (iv) define a symbol representing the function block type being created or modified; and a process builder configured to incorporate instances of one or more of the function block types into a control process and to provide the control process to a controller within a process control system, the process builder also configured to present at least one form to at least one user, each form associated with one of the function block types and based on the form layout for that function block type, each form allowing configuration of one of the instances of the function block types used in the control process; wherein the function block editor is configured to receive, through the graphical user interface, information identifying a pin exposure permission for one or more of the parameters of the function block type being created or modified, and wherein each pin exposure permission defines whether the associated parameter is assigned to a pin of the symbol representing the function block type being created or modified.