============================================================================||||
Document Prefix
============================================================================||||
# Comment
# lines
Document

----------------------------------------------------------------------------||||

(stream
 (comment)
 (comment)
 (document
  (flow_node
   (plain_scalar
    (string_scalar)))))

============================================================================||||
Document Markers
============================================================================||||
%YAML 1.2
---
Document
... # Suffix

----------------------------------------------------------------------------||||

(stream
 (document
  (yaml_directive
   (yaml_version))
  (flow_node
   (plain_scalar
    (string_scalar))))
 (comment))

============================================================================||||
Bare Documents
============================================================================||||
Bare
document
...
# No document
...
|
%!PS-Adobe-2.0 # Not the first line

----------------------------------------------------------------------------||||

(stream
 (document
  (flow_node
   (plain_scalar
    (string_scalar))))
 (comment)
 (document)
 (document
  (block_node
   (block_scalar))))

============================================================================||||
Explicit Documents
============================================================================||||
---
{ matches
% : 20 }
...
---
# Empty
...

----------------------------------------------------------------------------||||

(stream
 (document
  (flow_node
   (flow_mapping
    (flow_pair
     (flow_node
      (plain_scalar
       (string_scalar)))
     (flow_node
      (plain_scalar
       (integer_scalar)))))))
 (document
  (comment)))

============================================================================||||
Directives Documents
============================================================================||||
%YAML 1.2
--- |
%!PS-Adobe-2.0
...
%YAML1.2
---
# Empty
...

----------------------------------------------------------------------------||||

(stream
 (document
  (yaml_directive
   (yaml_version))
  (block_node
   (block_scalar)))
 (document
  (reserved_directive
   (directive_name))
  (comment)))

============================================================================||||
Stream
============================================================================||||
Document
---
# Empty
...
%YAML 1.2
---
matches %: 20

----------------------------------------------------------------------------||||

(stream
 (document
  (flow_node
   (plain_scalar
    (string_scalar))))
 (document
  (comment))
 (document
  (yaml_directive
   (yaml_version))
  (block_node
   (block_mapping
    (block_mapping_pair
     (flow_node
      (plain_scalar
       (string_scalar)))
     (flow_node
      (plain_scalar
       (integer_scalar))))))))