The valueOf() method of Temporal.PlainTime instances throws a TypeError, which prevents Temporal.PlainTime instances from being implicitly converted to primitives when used in arithmetic or comparison operations.

Syntax

valueOf()

Parameters

None.

Return value

None.

Exceptions

TypeError

Always thrown.

Description

Because both primitive conversion and number conversion call valueOf() before toString(), if valueOf() is absent, then an expression like time1 > time2 would implicitly compare them as strings, which may have unexpected results. By throwing a TypeError, Temporal.PlainTime instances prevent such implicit conversions. You need to explicitly convert them to strings using Temporal.PlainTime.prototype.toString(), or use the Temporal.PlainTime.compare() static method to compare them.

Examples

Arithmetic and comparison operations on Temporal.PlainTime

All arithmetic and comparison operations on Temporal.PlainTime instances should use the dedicated methods or convert them to primitives explicitly.

const time1 = Temporal.PlainTime.from("00:00:00");
const time2 = Temporal.PlainTime.from("12:00:00");
time1 > time2; // TypeError: can't convert PlainTime to primitive type
Temporal.PlainTime.compare(time1, time2); // -1

time2 - time1; // TypeError: can't convert PlainTime to primitive type
time2.since(time1).toString(); // "PT12H"

Specifications

Browser compatibility

See also

• Temporal.PlainTime
• Temporal.PlainTime.prototype.toString()
• Temporal.PlainTime.prototype.toJSON()
• Temporal.PlainTime.prototype.toLocaleString()