df_ptype2() and df_cast() are the two functions you need to
call from vec_ptype2() and vec_cast() methods for data frame
subclasses. See ?howto-faq-coercion-data-frame.
Their main job is to determine the common type of two data frames,
adding and coercing columns as needed, or throwing an incompatible
type error when the columns are not compatible.
df_ptype2(x, y, ..., x_arg = "", y_arg = "", call = caller_env())df_cast(x, to, ..., x_arg = "", to_arg = "", call = caller_env())
tib_ptype2(x, y, ..., x_arg = "", y_arg = "", call = caller_env())
tib_cast(x, to, ..., x_arg = "", to_arg = "", call = caller_env())
When x and y are not compatible, an error of class
vctrs_error_incompatible_type is thrown.
When x and y are compatible, df_ptype2() returns the common
type as a bare data frame. tib_ptype2() returns the common type
as a bare tibble.
Subclasses of data frame.
If you call df_ptype2() or df_cast() from a
vec_ptype2() or vec_cast() method, you must forward the dots
passed to your method on to df_ptype2() or df_cast().
Argument names for x and y. These are used
in error messages to inform the user about the locations of
incompatible types (see stop_incompatible_type()).
The execution environment of a currently
running function, e.g. caller_env(). The function will be
mentioned in error messages as the source of the error. See the
call argument of abort() for more information.
Argument name to used in error messages to
inform the user about the locations of incompatible types
(see stop_incompatible_type()).