Did you know ... Search Documentation:
Pack xlibrary -- prolog/atomics_atom.pl
PublicShow source
 atomics_atom(+Atms:list(atomic), -Atm:atom) is det
atomics_atom(?Atms:list(atom), +Atm:atomic)
Atm is the atom resulting from concatenating all atomics in the list Atms in the order in which they appear. If Atm is an atom at call then Atms can contain free variables, and multiple solutions can be found on backtracking.

Based on atom_concat/2 of Ciao-Prolog, but without performance issues.