Previous: Display Margins, Up: Display Property
You can make any display specification conditional. To do that,
package it in another list of the form (when
condition .
spec)
. Then the specification spec applies only when
condition evaluates to a non-nil
value. During the
evaluation, object
is bound to the string or buffer having the
conditional display
property. position
and
buffer-position
are bound to the position within object
and the buffer position where the display
property was found,
respectively. Both positions can be different when object
is a
string.