tracef

tracef( 
[ s_function | t_fileName ... | t ]
) 
=> g_result

Description

Turns on tracing of specified functions. Shows the functions called with their evaluated arguments and return values. This is an nlambda function.

The output port for tracing is ptport, which defaults to poport.

• If t is passed in, all functions are traced. However, this probably produces more information than you want and your program runs much more slowly.
• If you do not give tracef an argument, it returns a list of all functions being traced.
• If the argument is a string, tracef assumes it is a file name. tracef checks to see if a file was loaded after debug mode was turned on and if so, traces all functions defined in that file.
• If the symbol debugFiles is passed in, all functions in all files loaded since debug mode was turned on are traced.

If you want to force certain functions not to be traced even though you have turned on tracing for many or all functions, you can add the property notrace with a non-nil value on the name of the function. For example, to prevent plus from being traced use putprop('plus t 'notrace ) or plus.notrace = t.

Arguments

s_function	Any function that you want to trace.
t_filename	Any file containing functions that you want to trace.
t	Turns tracing on for all functions.

Value Returned

g_result

Functions or files traced.

Examples

(defun f (x) (add1 x))    ; Defines a function f.
=> f

(tracef f                 ; Turns on tracing for f.
=> (f)

f(3) 
|f(3)
|f --> 4
=> 4

(tracef t                 ; Turns on tracing for all functions.
|tracef --> t
=> t

f(3)
|f(3)
||add1(3)
||add1 --> 4
|f --> 4
=> 4

Suppose testfuns.il defines functions f1 and f2:

(defun f1 (x) x+1)
(defun f2 (y) f1(y)+1)

installDebugger           ; debug was turned on before loading a file
=> t

1> load "testfuns.il"
=> t

1> tracef("testfuns.il") 
                         ; tracing for all functions in the file
("testfuns.il")

1> f2 3
|f2(3)
||f1(3)
||f1 --> 4
|f2 --> 5
5

Related Topics

Debug Functions

tracev

untrace

untracev

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