Always returns 0 because a Field can't be a Record, so it can't
contain any members.
Returns the value component of this Field.
Converts the value of this Field into a boolean value, if possible.
Converts the value of this Field into a boolean value, if possible;
otherwise returns orElse if the value of this Field can't be converted
into a boolean value.
Always returns false because a Field can't be a Record, so it can't
have a Field member whose key is equal to the given key.
Always returns undefined because a Field can't be a Record, so it
can't have a head Attr whose value could be returned as a Record if
its key were equal to the tag.
Returns true if this Item always evaluates to the
same Item.
Always returns true because a Field can never be Absent.
Converts the value of this Field into a number value, if possible.
Converts the value of this Field into a number value, if possible;
otherwise returns orElse if the value of this Field can't be converted
into a number value.
Converts the value of this Field into a string value, if possible.
Converts the value of this Field into a string value, if possible;
otherwise returns orElse if the value of this Field can't be converted
into a string value.
Always returns undefined because a Field can't be a Record, so it
can't have a first member Attr whose key string could be returned.
Always returns an empty Record because a Field can't itself be a
Record, so it can't have any non-first members.
Always returns the value component of this Field.
Returns the value component of this Field.
Returns the heterogeneous sort order of this Item. Used to impose a
total order on the set of all items. When comparing two items of
different types, the items order according to their typeOrder}.
Returns a Record containing just this Field.
Returns the key component of this
Field.