This icon accepts a macro program as input and builds a user interface ready to accept user input. The user enters the required input in this interface, saves and on a given icon action, the embedded macro program is executed.
The input macro program must contain a specific code to define the user interface and parse of the input.
The Macro Parameters Editor
The Macro Parameters editor is dynamic in that its layout and contents are determined by the user depending on what is specified in the macro program the user provides. The rationale is that the editor contents form a user interface accepting variable user input for execution by the macro provided. It is a circular process in that the Macro icon passed to the Macro Parameters specifies the user interface, the Macro Parameters builds it, accepts the input and passes it back to the Macro icon to be used in whatever calculations it specifies.
The editor only contains one field called Macro. When a Macro icon is dropped here the user interface defined by it is automatically built inside the editor.