Marks the named items for tracing. A message is printed whenever a traced procedure is invoked, giving the actual input values, and whenever a traced procedure runs STOP or OUTPUT. A message is printed whenever a new value is assigned to a traced variable using MAKE. A message is printed whenever a new property is given to a traced property list using PPROP.
TRACE does not throw an error if it is asked to trace a procedure, variable, or property list that is not in the workspace, but doing so has no effect. TRACE also does not throw an error if asked to trace a primitive, but this also has no effect.
See the Workspace Queries section for an explanation of the
TO MYPRINT :a PRINT :a END MYPRINT "HelloHello
TRACE "MYPRINT MYPRINT "Hello( MYPRINT "Hello ) Hello
UNTRACE "MYPRINT MYPRINT "HelloHello
|The Trace Button|