11.3.18 atom_concat/3   ISO

Synopsis

atom_concat(+Atom1,+Atom2,-Atom12)

atom_concat(-Atom1,-Atom2,+Atom12)

The characters of the atom Atom1 concatenated with those of Atom2 are the same as the characters of atom Atom12.

Arguments

Atom1

atom

Atom2

atom

Atom12

atom

Description

Initially, either both Atom1 and Atom2, or Atom12, must be instantiated to atoms. If only Atom12 is instantiated, then nondeterminately enumerates all possible atom-pairs that concatenate to the given atom, e.g.:

| ?- atom_concat(A, B, 'ab').

A = '',
B = ab ? ;

A = a,
B = b ? ;

A = ab,
B = ''  ;

no

Exceptions

instantiation_error

The last argument is uninstantiated and at the same time either (or both) of the first two arguments are uninstantiated.

type_error

An instantiated argument is not an atom.

representation_error

Atom12 is too long to be represented.

See Also

atom_length/2, sub_atom/5.