browser {base} | R Documentation |
Interrupt the execution of an expression and allow the inspection of
the environment where browser
was called from.
browser()
A call to browser
can be included in the body of a function.
When reached, this causes a pause in the execution of the
current expression and allows access to the R interpreter.
At the browser prompt the user can enter commands or R expressions. The commands are
c
(or just return) exit the browser and continue execution at the next statement.
cont
synonym for c
.
n
enter the step-through debugger. This changes the
meaning of c
: see the documentation for debug
.
where
print a stack trace of all active function calls.
Q
exit the browser and the current evaluation and return to the top-level prompt.
(Leading and trailing whitespace is ignored, except for return).
Anything else entered at the browser prompt is interpreted as an
R expression to be evaluated in the calling environment: in
particular typing an object name will cause the object to be printed,
and ls()
lists the objects in the calling frame. (If you want
to look at an object with a name such as n
, print it
explicitly.)
The number of lines printed for the deparsed call can be limited by
setting options(deparse.max.lines)
.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.
Chambers, J. M. (1998) Programming with Data. A Guide to the S Language. Springer.
debug
, and
traceback
for the stack on error.