fastn provides two types of access modifiers which can be used with component arguments. If not specified, then the default visibility is public for all arguments defined under component definition.

• public (Default): This ensures that the arguments can be accessed from anywhere.
• private: This ensures that the argument can only be accessed from within the component.

To use any access modifier, you simply need to specify it while defining component argument during component definition.

-- component foo:
caption name:
private boolean mouse-hovered: false

-- ftd.text: $foo.name
color: red
color if { foo.mouse-hovered }: green
$on-mouse-enter$: $ftd.set-bool($a = $foo.mouse-hovered, v = true)
$on-mouse-leave$: $ftd.set-bool($a = $foo.mouse-hovered, v = false)

-- end: foo

-- component foo:
caption name:
private boolean mouse-hovered: false

-- ftd.text: $foo.name
color: red
color if { foo.mouse-hovered }: green
$on-mouse-enter$: $ftd.set-bool($a = $foo.mouse-hovered, v = true)
$on-mouse-leave$: $ftd.set-bool($a = $foo.mouse-hovered, v = false)

-- end: foo

;; This should not be done
-- foo: xyz
$mouse-hovered: false

;; This should not be done
-- foo: xyz
$mouse-hovered: false