Validate and format a function call for use in error messagesSource:
error_call()takes either a frame environment or a call. If the input is an environment,
frame_call()with some additional logic, e.g. for S3 methods and for frames with a
format_error_call()simplifies its input to a simple call (see section below) and formats the result as code (using cli if available). Use this function to generate the "in" part of an error message from a stack frame call.
format_error_call()first passes its input to
error_call()to fetch calls from frame environments.
The arguments of function calls are stripped.
Complex function calls containing inlined objects return
ifpreserve the condition since it might be informative. Branches are dropped.
Calls to operators and other special syntax are formatted using their names rather than the potentially confusing function form.
# Arguments are stripped writeLines(format_error_call(quote(foo(bar, baz)))) #> `foo()` # Returns `NULL` with complex calls such as those that contain # inlined functions format_error_call(call2(list)) #> NULL # Operators are formatted using their names rather than in # function call form writeLines(format_error_call(quote(1 + 2))) #> `1 + 2`