The Number()
constructor creates Number
objects. When called as a function, it returns primitive values of type Number.
The Number()
constructor creates Number
objects. When called as a function, it returns primitive values of type Number.
Note: Number()
can be called with or without new
, but with different effects. See Return value.
value
The numeric value of the object being created.
When Number
is called as a constructor (with new
), it creates a Number
object, which is not a primitive.
When Number
is called as a function, it coerces the parameter to a number primitive. BigInts are converted to numbers. If the value can't be converted, it returns NaN
.
Warning: You should rarely find yourself using Number
as a constructor.
Number()
is the only case where a BigInt can be converted to a number without throwing, because it's very explicit.
+1n; // TypeError: Cannot convert a BigInt value to a number 0 + 1n; // TypeError: Cannot mix BigInt and other types, use explicit conversions
Note that this may result in loss of precision, if the BigInt is too large to be safely represented.
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/Number