Originally posted by @stasm in #511 (comment)

I'm not sure if the spec is currently clear enough about the requirement to allow functions to inspect the raw value and the formatting options of their arguments. Specifically, while a function may eagerly format its operand to a string, it should (must?) also return the raw underlying value and the formatting options used for formatting, in case another function wants to extend them or use them for other logic. Consider:

local $a = {1 :number minIntegerDigits=3} // formats as 001.
local $b = {$a :number minFractionDigits=3} // formats as 001.000
// min integer digits are preserved from the previous call.

input {$item :noun case=accusative count=1}
local $colorMatchingGrammaticalNumberGenderCase = {$color :adjective accord=$item}
// :adjective inspects $item to learn about case=accusative, count=1