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Wrap a function with error handling and a structured log row

Source: R/add_trycatch_logrow.R
add_trycatch_logrow.Rd

Takes a function and returns a modified version that:

  • always returns a one-row data.frame (the "log row")

  • captures errors without stopping, recording the error message and the real traceback (call stack at the point of failure)

  • records wall-clock execution time

Usage

add_trycatch_logrow(f)

Arguments

f

A function to wrap.

Value

A function with the same formals as f, whose return value is a one-row data.frame with columns: all original arguments, success (logical), error_message (character or NA), traceback (character or NA), duration_secs (numeric).

Details

Why not plain tryCatch?

tryCatch() unwinds the call stack before entering the error handler. This means sys.calls() inside a tryCatch error handler returns the handler's own stack, not the stack that led to the error.

This function uses withCallingHandlers() (which fires while the original stack is still intact) to capture the traceback, then lets the error propagate to an outer tryCatch() for control flow.

Log row structure

The returned data.frame always has one row. Columns:

  • One column per formal argument of f, with the value passed

  • success: TRUE if the body executed without error

  • error_message: the error's conditionMessage(), or NA

  • traceback: the formatted call stack at the error, or NA

  • duration_secs: wall-clock seconds elapsed

Examples

safe_sqrt <- add_trycatch_logrow(function(x) sqrt(x))
safe_sqrt(4)    # success = TRUE, duration_secs > 0
#>   x success error_message traceback duration_secs
#> 1 4    TRUE          <NA>      <NA>             0
safe_sqrt("a")  # success = FALSE, error_message filled, traceback filled
#>   x success                                 error_message
#> 1 a   FALSE non-numeric argument to mathematical function
#>                                                                                                                                                                                                                                                                                                                                                                                                                                                                       traceback
#> 1 1. build_site(pkg, preview = FALSE, install = install, new_process = new_process, ...)\n2. build_site_local(pkg = pkg, examples = examples, run_dont_run = run_dont_run, seed = seed, lazy = lazy, override = o ...\n3. build_reference(pkg, lazy = lazy, examples = examples, run_dont_run = run_dont_run, seed = seed, override = override ...\n4. unwrap_purrr_error(purrr::map(topics, build_reference_topic, pkg = pkg, lazy = lazy, examples_env = examples_env, ru ...
#>   duration_secs
#> 1             0