letOrNull<T> function

T? letOrNull<T>(dynamic input)

Let's you convert input to a T type if possible, or returns null if the conversion cannot be performed.

Supported types:

• bool
• double
• int
• num
• String
• DateTime
• Duration
• FirestoreTimestamp (copy of Timestamp)
• Uri

Implementation

T? letOrNull<T>(dynamic input) {
  try {
    if (T == dynamic) return input;
    if (input == null && T != Null) return null;
    if (T == input.runtimeType) return input as T;
    if (typeEquality<T, double>() || typeEquality<T, double?>()) {
      return letDoubleOrNull(input) as T;
    } else if (typeEquality<T, int>() || typeEquality<T, int?>()) {
      return letInt(input) as T;
    } else if (typeEquality<T, num>() || typeEquality<T, num?>()) {
      return letNumOrNull(input) as T;
    } else if (typeEquality<T, bool>() || typeEquality<T, bool?>()) {
      return letBoolOrNull(input) as T;
    } else if (typeEquality<T, DateTime>() || typeEquality<T, DateTime?>()) {
      return letDateTimeOrNull(input) as T;
    } else if (typeEquality<T, FirestoreTimestamp>() ||
        typeEquality<T, FirestoreTimestamp?>()) {
      return letFirestoreTimestampOrNull(input) as T;
    } else if (typeEquality<T, Duration>() || typeEquality<T, Duration?>()) {
      return letDurationOrNull(input) as T;
    } else if (typeEquality<T, Uri>() || typeEquality<T, Uri?>()) {
      return letUriOrNull(input) as T;
    } else if (typeEquality<T, String>() || typeEquality<T, String?>()) {
      return input?.toString() as T;
    }
    return input as T;
  } catch (_) {}
  return null;
}