- atom(X):
The term X is an atom.
- atomic(X):
The term X is an atom or a number.
- float(X):
The term X is a floating-point number.
- real(X):
This is the same as float(X).
- integer(X):
The term X is an integer.
- number(X):
The term X is a number.
- nonvar(X):
The term X is not a variable.
- var(X):
The term X is a free variable.
- compound(X):
The term X is a compound term. This predicate is true if X is either a structure or a list.
- ground(X):
The term X is ground.
- callable(X):
The term X is a callable term, i.e., an atom or a compound term. Type errors will not occur in a meta-call, such as call(X) if X is callable. Note that a callable term does not mean that the predicate is defined.
Neng-Fa Zhou
2013-01-25
