grammar, possibly misleading

[Velumuthali]

Enumerations
"An enum where no constructors contain fields are called a field-less enum."

1. grammar: are called may be changed to is called.
2. possibly misleading:
   "where no constructors" . The plural 'constructors' suggests that more than one constructor is allowed.
   My idea:
   If an enum constructor contains no fields, the enum is called a field-less enum.

[bjorn3]

For 2: Each variant of an enum has it's own constructor. None of these may have any fields for the enum as a whole to be called a field-less enum.

[Velumuthali]

Sir bjorn3, Thank you for pointing out the inexactness my suggestion. I stand corrected. But I humbly feel "Each variant of an enum has it's own constructor" is suspicious.
This may do better:
For 2 If every variant of an enum that has a constructor has no field in the constructor, then the enum is called a field-less enum.

[ahmed-mohamed-eng]

@bjorn3 As a non-native speaker I agree with @Velumuthali on his/her suggestion.