For internal use by the placeholder_format
tweak.
make_placeholder_fun(pattern)
[character(1)]
Any character, optionally followed by 1
or name
. Examples: "?"
, "$1"
, ":name"
[function(n)]
A function with one argument n
that
returns a vector of length n
with placeholders of the specified format.
Examples: ?, ?, ?, ...
, $1, $2, $3, ...
, :a, :b, :c