cnd-entrace.md
In rlang: Functions for Base Types and Core R and 'Tidyverse' Features

rlang and base errors are properly entraced

Code
  cat_line(base)
Output
  Error in h() : foo
  Calls: f -> g -> h
  Run `rlang::last_trace()` to see where the error occurred.
  <error/rlang_error>
  Error:
  ! foo
  ---
  Backtrace:
      x
   1. \-global f()
   2.   \-global g()
   3.     \-global h()
  <error/rlang_error>
  Error:
  ! foo
  ---
  Backtrace:
      x
   1. \-global f()
   2.   \-global g()
   3.     \-global h()
Code
  cat_line(rlang)
Output
  Error in `h()`:
  ! foo
  Run `rlang::last_trace()` to see where the error occurred.
  <error/rlang_error>
  Error in `h()`:
  ! foo
  ---
  Backtrace:
      x
   1. \-global f()
   2.   \-global g()
   3.     \-global h()
  Run rlang::last_trace(drop = FALSE) to see 1 hidden frame.
  <error/rlang_error>
  Error in `h()`:
  ! foo
  ---
  Backtrace:
      x
   1. \-global f()
   2.   \-global g()
   3.     \-global h()
  Run rlang::last_trace(drop = FALSE) to see 1 hidden frame.

can supply handler environment as `bottom`

Code
  print(err)
Output
  <error/rlang_error>
  Error in `1 + ""`:
  ! non-numeric argument to binary operator
  ---
  Backtrace:
       x
    1. +-rlang::catch_cnd(...)
    2. | +-rlang::eval_bare(...)
    3. | +-base::tryCatch(...)
    4. | | \-base (local) tryCatchList(expr, classes, parentenv, handlers)
    5. | |   \-base (local) tryCatchOne(expr, names, parentenv, handlers[[1L]])
    6. | |     \-base (local) doTryCatch(return(expr), name, parentenv, handler)
    7. | \-base::force(expr)
    8. +-base::withCallingHandlers(...)
    9. \-rlang (local) f()
   10.   \-rlang (local) g()
   11.     \-rlang (local) h()
   12.       \-base::identity(1 + "")

can set `entrace()` as a global handler

Error in `1 + ""`:
! non-numeric argument to binary operator
Backtrace:
    x
 1. \-global f()
 2.   \-global g()
 3.     \-global h()
Execution halted

Error in `1 + ""`:
! non-numeric argument to binary operator
Backtrace:
    x
 1. \-global f()
 2.   \-global g()
 3.     \-global h()
Execution halted

FOO
Warning in g() : bar
baz
> rlang::last_warnings()
[[1]]
<warning/rlang_warning>
Warning in `f()`:
foo
---
Backtrace:
    x
 1. \-global f()

[[2]]
<warning/rlang_warning>
Warning in `g()`:
bar
---
Backtrace:
    x
 1. \-global f()
 2.   \-global g()


> rlang::last_warnings(2)
[[1]]
<warning/rlang_warning>
Warning in `f()`:
foo
---
Backtrace:
    x
 1. \-global f()

[[2]]
<warning/rlang_warning>
Warning in `g()`:
bar
---
Backtrace:
    x
 1. \-global f()
 2.   \-global g()


> summary(rlang::last_messages())
[[1]]
<message/rlang_message>
Message in `message()`:
FOO
---
Backtrace:
    x
 1. \-global f()

[[2]]
<message/rlang_message>
Message in `message()`:
baz
---
Backtrace:
    x
 1. \-global f()
 2.   \-global g()
 3.     \-global h()


> summary(rlang::last_messages(1))
[[1]]
<message/rlang_message>
Message in `message()`:
baz
---
Backtrace:
    x
 1. \-global f()
 2.   \-global g()
 3.     \-global h()

Warning message:
In f() : foo

can call `global_entrace()` in knitted documents

Code
  cat_line(entrace_lines)
Output
      options(
        rlang_backtrace_on_error_report = "full"
      )

      f <- function(do = stop) g(do)
      g <- function(do) h(do)
      h <- function(do) do("foo")

      f()

      ## Error in h(do): foo

      rlang::global_entrace()

      f()

      ## Error in `h()`:
      ## ! foo
      ## Backtrace:
      ##     x
      ##  1. \-rlang (local) f()
      ##  2.   \-rlang (local) g(do)
      ##  3.     \-rlang (local) h(do)

      f(warning)

      ## Warning in h(do): foo

      options(
        rlang_backtrace_on_warning_report = "full"
      )

      f(warning)

      ## Warning in h(do): foo
      ## Backtrace:
      ##     x
      ##  1. \-rlang (local) f(warning)
      ##  2.   \-rlang (local) g(do)
      ##  3.     \-rlang (local) h(do)

      rlang::last_warnings()

      ## [[1]]
      ## <warning/rlang_warning>
      ## Warning in `h()`:
      ## foo
      ## ---
      ## Backtrace:
      ##     x
      ##  1. \-rlang (local) f(warning)
      ##  2.   \-rlang (local) g(do)
      ##  3.     \-rlang (local) h(do)
      ## 
      ## [[2]]
      ## <warning/rlang_warning>
      ## Warning in `h()`:
      ## foo
      ## ---
      ## Backtrace:
      ##     x
      ##  1. \-rlang (local) f(warning)
      ##  2.   \-rlang (local) g(do)
      ##  3.     \-rlang (local) h(do)

can't set backtrace-on-warning to reminder

Code
  peek_backtrace_on_warning_report()
Condition
  Warning:
  `rlang_backtrace_on_warning_report` must be one of `c("none", "branch", "full")`.
  i The option was reset to "none".
Output
  [1] "none"