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writeln(+Stream, ?Term)

The term Term is written on the output stream Stream according to the current operator declarations. Equivalent to write(Stream,Term), nl(Stream).
Stream
Stream handle or alias (atom)
Term
Prolog term.

Description

Used to write the term Term (followed by a newline) on the output stream Stream according to the current operator declarations.

Modes and Determinism

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Exceptions

(4) instantiation fault
Stream is not instantiated.
(5) type error
Stream is not an atom or a stream handle.
(192) illegal stream mode
Stream is not an output stream.
(193) illegal stream specification
Stream is an illegal stream specification.

Examples

   Success:
      ?- open(file1,update,s), writeln(s, X + 2),
         writeln(s, Y + 3), close(s).
      X = _90
      Y = _78
      yes.
      ?- sh('cat file1').
      _90 + 2
      _78 + 3
      yes.

Error:
      writeln(S, a(b,c)).        (Error 4).
      writeln("string", a(b,c)). (Error 5).
      writeln(9, X + 2).         (Error 192).
      writeln(atom, X + 2).      (Error 193).

See Also

writeln / 1, write / 1, write / 2