Object.hasOwn(map, key) return true or false based on the existence of the property in the map.- Advantages over using conditionals over
map[key]
- If the value of that key is falsy it will go in the falsy condition even if the key exists in the map
const BRAND_MARKET_SHARE_MAPPING = {
'Brand A': 0, // Market share is 0%
'Brand B': 4.3,
};
const brand = { name: 'Brand A' };
// Using direct access:
BRAND_MARKET_SHARE_MAPPING[brand.name] && {
label: 'Market Share',
value: '0%',
};
// This will not include the object because 0 is falsy.
// Using Object.hasOwn:
Object.hasOwn(BRAND_MARKET_SHARE_MAPPING, brand.name) && {
label: 'Market Share',
value: '0%',
};
// This will correctly include the object because the property exists.
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