Register a pairwise calendar conversion override — register_calendar

By default recast_calendar() routes every conversion through the shared instant grid (A -> base -> B). A registered override short-circuits that route for one named calendar pair — the escape hatch for exact nested-calendar arithmetic or anything the grid cannot express.

Usage

register_calendar_conversion(from, to, fun)

get_calendar_conversion(from, to)

list_calendar_conversions()

clear_calendar_conversions(key = NULL)

Arguments

from, to: Calendar names (meta$name) the override applies to.
fun: A function with signature fun(x, from, to, ...) receiving the same arguments as recast_calendar() and returning the recast data.frame. NULL removes a previously registered override.
key: Optional character vector of "from->to" keys to remove; NULL (default) clears everything.

Value

Invisibly, the registry key ("from->to").

get_calendar_conversion() returns the registered function or NULL.

list_calendar_conversions() returns a data.frame with column key.

Examples

register_calendar_conversion("m12", "q4", function(x, from, to, ...) {
  # trivial exact nesting: quarters are consecutive month triples
  q <- rep(sprintf("Q%d", 1:4), each = 3)
  stats::aggregate(x[-1], list(timeslice = q[match(x$timeslice,
    S7::prop(from, "leaftable")$timeslice)]), sum)
})
"m12->q4" %in% list_calendar_conversions()$key
#> [1] TRUE
clear_calendar_conversions()