make_opt | R Documentation |
Make an existing function accepting and returning optionals.
make_opt(fun, stop_if_none = FALSE, fun_if_none = NULL)
fun |
The function to make optional, might be any function. |
stop_if_none |
If true, |
fun_if_none |
If not null, will be executed if an argument
is |
Every optional argument passed to f_opt()
will be
converted to its original type before being sent
to f()
. If one or more of them is none
,
several behaviors are available (see argument list).
If f()
returns null, or if an error is thrown
during its execution, then f_opt()
returns
none
. Else it will return option(f(...))
.
The optional function. To be used with the
same parameters than fun()
.
option(), none(), match_with()
c_opt <- make_opt(c) c_opt(option(2), none, option(5)) ## [1] 2 5 c_opt() ## [1] "None"
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