FormPage
FormPage[formspec,func] represents an active page that takes input from a form and generates results on the same page by applying func to the values obtained from the form whose structure is defined by formspec.
FormPage[{name1->type1,…},func] represents an active form page with fields named namei interpreted as types typei.
FormPage[{{name1,label1}->type1,…},func] uses labeli as the label for the field named namei.
FormPage[{namespec1->type1->default1,…},func] uses defaulti as the default for the field specified by namespeci.
FormPage[formspec,func,form] lays out the page according to the layout specification form.
FormPage[formspec,func,initform->resform] uses initform as the initial layout specification and resform as the layout specification for result pages.
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