anchor.diff:  
   `==` (equal, case-sensitive)::
   Returns `true` if the values to the left and right of the operator are equal.
  -Otherwise returns `false`. For strings, matching is case-sensitive.
  +Otherwise returns `false`. For strings, matching is case-sensitive. Wildcards
  +are not supported.
   
   `:` (equal, case-insensitive)::
   Returns `true` if strings to the left and right of the operator are equal.
   Otherwise returns `false`. Matching is case-insensitive and can only be used to
  -compare strings.
  +compare strings. <<eql-syntax-wildcards,Wildcards>> are supported.
   
   [IMPORTANT]
   ====
  
positive.code: `!=` (not equal, case-sensitive)::
  Returns `true` if the values to the left and right of the operator are not
  equal. Otherwise returns `false`. For strings, matching is case-sensitive.
  
  `>=` (greater than or equal) ::
  Returns `true` if the value to the left of the operator is greater than or equal
  
negative.code: ----
  
  [discrete]
  [[eql-syntax-wildcards]]
  ===== Wildcards
  
  For string comparisons using the `:` operator, you can use wildcards (`*`) to
  match specific patterns:
  
  [source,eql]
  ----
  field : "example*wildcard"
  field : "*example-wildcard"
  field : "example-wildcard*"
  ----
  
  [discrete]
  [[eql-sequences]]
  === Sequences
  
  