A configuration value may be defined as a function such that it takes, in effect, a temporary default value until it is merged on the web-page. When activated, the actual value used is calculated from the expressions in the Configuration file.

1.Open the document in EscapeE to attach a plugin to a new field: see To attach a plugin.
2.Click the Configure button to display the script configuration dialog.
3.Enter an expression in the New configuration string edit box. This may take either of these two forms:
oscript: expression or
oscript:fieldname:=expression
4.Click OK.