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trace

Execute subsequent top-level queries with the debugger on.

Description

If the debugger is already on, no effect. If not, the debugger will be switched on at the next top-level query. The debugger will stay on until it is switched off with notrace/0.

The debugger will stop at the first traceable port.

This is not actually a predicate but a toplevel-command.

Modes and Determinism

Examples

[eclipse 1]: [user].
p :- true, writeln(hello).
user       compiled traceable 68 bytes in 0.00 seconds

yes.
[eclipse 2]: trace.
Debugger switched on - creep mode
[eclipse 3]: p.
  (1) 1 CALL  p   %> creep
S (2) 2 CALL  writeln(hello)   %> creep
hello
S (2) 2 EXIT  writeln(hello)   %> creep
  (1) 1 EXIT  p   %> creep

yes.

See Also

debug / 0, debug / 1, notrace / 0, trace / 1