gensym/2

Module: builtins

gensym/2 — generates families of unique symbolsr

FORMS

gensym(Prefix, Symbol)

DESCRIPTION

If Prefix is a symbol (either an interned or uninterned atom), then Symbol is a new UIA which has not previously existed in the system and which involves Prefix as a subsymbol. . The string also involves the system time that the current ALS Prolog image was started, together with the value of a counter for these generated symbols. Consequently, the symbols are almost guaranteed to be unique across invokations of the system, execpt for the possibility of the system clock wrapping around.

EXAMPLES

?- gensym('<Prefix>', Symbol).

Symbol='?<Prefix>_1540251652_0' 

yes.

?- gensym(airplane, X).

X=?airplane_1540251652_1

yes.