Why return failure when "deviate delete" a "mandatory" statement ?

[lyzliyuzhi91]

https://github.com/CESNET/libyang/blob/fc4dbd923e044006c93df020590a1e5a8656c09e/src/parser_yang.c#L3955

Why success for "must" but failure for "mandatory"/"min-element"/... ? thanks

[michalvasko]

In short, because in deviate-delete-stmt there is no mandatory in the YANG ABNF.