LookupInSpec.exists constructor
Creates a LookupInSpec for fetching whether a specific field exists in the document.
path
must be a String or LookupInMacro.
When xattr
is true
, this operation references the extended attribute
data of the document. Otherwise, it references the document body.
Defaults to false
.
Implementation
factory LookupInSpec.exists(Object path, {bool? xattr}) =>
LookupInSpec._create(Opcode.exists, path, xattr: xattr);