* >$S ( a.str -- $: a$ )

Push the external Forth string a.str onto the string stack, without
copying the string value into the string buffer. It is an unchecked
error if the Forth string a.str is not stored as an external packed
string. "to-string-s"
WARNING: If the string value of a.str is actually in the string 

buffer, the push operation may generate a garbage collection
that invalidates its PSA.

dstrings ordinary primitive