coerce static method

dynamic coerce(dynamic instance, ClassMirror targetClass, { dynamic coerce(dynamic o, ClassMirror tClass)?, })

Coerces the given object to the specified class (targetClass). *

• • coerce - used to coerce the given object to the given type.
• If omitted or null is returned, the default coercion will be done (it
• handles the basic types: int, double, String, num, and Datetime).
• It throws CoercionError if failed to coerce.

Implementation

static coerce(instance, ClassMirror targetClass,
    {coerce(o, ClassMirror tClass)?}) {
  if (coerce != null) {
    final o = coerce(instance, targetClass);
    if (o != null)
      return o;
  }
  if (instance == null)
    return instance;

  final clz = reflect(instance).type;
  if (isAssignableFrom(targetClass, clz))
    return instance;

  var sval = instance.toString();
  if (targetClass == Mirror.String)
    return sval;
  if (sval.isEmpty)
    return null;
  if (targetClass == Mirror.int)
    return int.parse(sval);
  if (targetClass == Mirror.double)
    return double.parse(sval);
  if (targetClass == Mirror.num)
    return sval.contains('.') ? double.parse(sval): int.parse(sval);
  if (targetClass == Mirror.DateTime)
    return DateTime.parse(sval);
  if (targetClass == Mirror.bool)
    return !sval.isEmpty && (sval = sval.toLowerCase()) != "false" && sval != "no"
      && sval != "off" && sval != "none";
  throw CoercionError(instance, targetClass);
}