check the environment for a property, usually
a condition like questioning the existance of
specified wordset, but it can also return some
implementation properties like "WORDLISTS"
(the length of the search-order) or "#LOCALS"
(the maximum number of locals)
Here it implements the environment queries as a SEARCH-WORDLIST in a user-visible vocabulary called ENVIRONMENT
: ENVIRONMENT?
['] ENVIRONMENT >WORDLIST SEARCH-WORDLIST
IF EXECUTE TRUE ELSE FALSE THEN ;