3 ms·

Well, yes, of course. The thing you could previously rely on being present can no longer be guaranteed to be present - that _should_ require code in the calling

• nickbauman 6y ago
  Not if I loosened the requirement. Stricter adherents shouldn't have to change anything. This is poor language ergonomics.
  • setr 6y ago
    To be clear, you're talking about the function signature changing from fn(a: int) to fn(a: Option<int>) ? Technically, yes, all callers would have to update, but practically, you'd just define fn(a: int) { fn_2(Some(a)) } to avoid the breakage. That is, you're essentially telling the compiler how to loosen the requirements. Ergonomically, this seems rather fine. Especially if this means you gain (some) protections from the much more problematic case of restricting the requirements.
    • mqus 6y ago
      There is also the Option of accepting Into<Option<T>>, which does cover both variants and is completely backwards compatible.