org-maybe-intangible

org-maybe-intangible is a Lisp macro in `org-macs.el'.

(org-maybe-intangible PROPS)

Add '(intangible t) to PROPS if Emacs version is earlier than Emacs 22.
In Emacs 21, invisible text is not avoided by the command loop, so the
intangible property is needed to make sure point skips this text.
In Emacs 22, this is not necessary. The intangible text property has
led to problems with flyspell. These problems are fixed in flyspell.el,
but we still avoid setting the property in Emacs 22 and later.
We use a macro so that the test can happen at compilation time.