Learn Red - Fundamentals of Red

Using do in view

Inside the view code block, ordinary binding statements such as n: 2 ** 3 and print n must be placed within a do block, like this:

;-- see Chapter09/container-layout.red:view [    text "Use of do block"    do [n: 2 ** 3 print n]]

A do block can be used to evaluate code and initialize or make changes to the GUI, before the layout is displayed.

All other code must appear within action facet code blocks, such as our button-click code [download-rates].