4.16 Property Lists
TBoS p.105-106, SD
Properly speaking property lists in Shen are property vectors, since vectors are used to store the information.
However usage from Common Lisp has made the term 'property list' part of the common currency of computing.
The application '(put object pointer value)' creates a pointer from the object to the value which can be retrieved by
'(get object pointer)'. 'put' denotes a destructive operation that uses hashing into a vector. Both 'put' and 'get' accept,
as an optional final argument, a vector into which all pointers are created.
(put mark sex male)
(get mark sex)
(get mark height)
value not found