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  • IsValidSimpleAssignmentTarget equivalent for delete?

IsValidSimpleAssignmentTarget equivalent for delete?

# Alan Schmitt (9 years ago)

Hello,

ES6 introduces IsValidSimpleAssignmentTarget to make an early error the attempt to assign to something that is obviously not a reference. For instance

#+begin_src javascript ((function () { throw 42 })()) = 3; #+end_src

is now a syntax error.

Is there a reason why the same does not apply to the delete operator, such as in the following ?

#+begin_src javascript delete ((function () { throw 42 })()) #+end_src

Thanks,

Alan

# Claude Pache (9 years ago)

Le 29 juil. 2015 à 19:28, Alan Schmitt <alan.schmitt at inria.fr> a écrit :

Hello,

ES6 introduces IsValidSimpleAssignmentTarget to make an early error the attempt to assign to something that is obviously not a reference. For instance

#+begin_src javascript ((function () { throw 42 })()) = 3; #+end_src

is now a syntax error.

Is there a reason why the same does not apply to the delete operator, such as in the following ?

#+begin_src javascript delete ((function () { throw 42 })()) #+end_src

Thanks,

Alan

The delete operator applied to a non-reference just does nothing (no error is thrown), whereas an assignment to a non-reference did throw an error. I guess that there is some BC risk for trying to turn a non-error into an early error, not worth the advantage?

# Alan Schmitt (9 years ago)

On 2015-07-31 06:26, Claude Pache <claude.pache at gmail.com> writes:

The delete operator applied to a non-reference just does nothing (no error is thrown), whereas an assignment to a non-reference did throw an error. I guess that there is some BC risk for trying to turn a non-error into an early error, not worth the advantage?

It makes sense. Thank you for the reply.

Alan