[<< wikibooks] Rebol Programming/header-rules
= USAGE: =
HEAD? series 


= DESCRIPTION: =
Returns TRUE if a series is at its head.
HEAD? is an action value.


= ARGUMENTS =
series -- (Type: series port)


= SOURCE CODE =
head?: native[
  "Returns TRUE if a series is at its head." 
  series [series! port!]
]