step.into.sysfuns: Set or get options for which "special" functions get stepped...

Description Usage Arguments Value Examples


When the debug package is in step-mode, there are a few special system functions that it can either step into, or leave the system to handle en bloc. These functions all have expression-type arguments. Currently, they are: try, suppressWarnings, eval, evalq, and (for built-in methods only) with and within. The step-into behaviour is controlled by calling step.into.sysfuns, which operates like par. You can also circumvent step-into at particular lines, by using go(n) to zoom through to the next statement. Additional methods for with and within can be handled via e.g. mtrace( with.myS3class), so are not considered "special" here.


# USAGE is not useful here-- see *Arguments*
step.into.sysfuns( ...)



tag-value pairs of logicals, e.g. with=TRUE, evalq=FALSE. Legal tags are shown in DESCRIPTION. If empty, return all tags-value pairs, as a logical vector.


Either the previous value(s) of tags that are set, or the entire logical vector of tags.


step.into.sysfuns() # all of them-- shows which are legal
step.into.sysfuns()['with'] # extract one of them
owith <- step.into.sysfuns( with=FALSE) # don't step into with-statements
step.into.sysfuns( with=owith) # revert to previous

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