React Native - invariant violation Objects are not valid as a react child

Question

I try to call my function an other component but i have this message :

Invariant Violation: Objects are not valid as a React child (found: object with keys {years, months, days})

My function age :

export const age = date => {
  const result = { years: 0, months: 0, days: 0 };
  const now = new Date();
  let age = parseISO(date);
  const years = differenceInYears(now, age);
  if (years > 0) {
    result.years = years;
    age = addYears(age, years);
  }
  const months = differenceInMonths(now, age);
  if (months > 0) {
    result.months = months;
    age = addMonths(age, months);
  }
  const days = differenceInDays(now, age);
  if (days > 0) {
    result.days = days;
  }
  return result;
};

That not possible to call this function ? Like that :

<Caption>
  {age(//key)}
</Caption> 

Answer 1

Your function can only return a string, you are returning an object. React doesn't know how to render it.

What you should probably do is this:

export const age = date => {
  const result = { years: 0, months: 0, days: 0 };
  const now = new Date();
  let age = parseISO(date);
  const years = differenceInYears(now, age);
  if (years > 0) {
    result.years = years;
    age = addYears(age, years);
  }
  const months = differenceInMonths(now, age);
  if (months > 0) {
    result.months = months;
    age = addMonths(age, months);
  }
  const days = differenceInDays(now, age);
  if (days > 0) {
    result.days = days;
  }
return `${result.years} years ${result.months} ${result.days}`
};