This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
toSource() method returns code that could eval to the same error.
A string containing the source code of the error.
toSource method of an
Error instance (includingNativeErrors) will return a string containing the source code of the error. This string can be evaluated to create an (approximately) equal object. Naturally, the string containing the source follows the structure of the
Error constructor. For example:
where these attributes correspond to the respective properties of the error instance.
Note: Be aware that the properties used by the
toSource method in the creation of this string are mutable and may not accurately reflect the function used to create an error instance or the filename or line number where the actual error occurred.