I submitted a bug report (https://github.com/ingydotnet/yaml-pm/issues/167) to YAML's Gitlab repo.

Some of the highlights are: 
YAML Error: Inconsistent indentation level
Code: YAML_PARSE_ERR_INCONSISTENT_INDENTATION
Line: 114
PROBLEM:
> is: [
> searchable: {description: "with valid searchable fields: > songTitle
+", example: "["songTitle", "Get L", "like"]"},
> orderable: {fieldsList: "songTitle"},
> pageable
> ]

YAML Error: Invalid element in map
Code: YAML_LOAD_ERR_BAD_MAP_ELEMENT
Line: 122
PROBLEM:
> /{songId}:

YAML Error: Can't parse inline sequence
Code: YAML_PARSE_ERR_INLINE_SEQUENCE
Line: 174

PROBLEM:
> /albums:
> type:
> collection:
> exampleCollection: !include jukebox-include-albums.sample
> exampleItem: !include jukebox-include-album-new.sample

[download]

The Perl project mentioned on RAML's website (https://github.com/spq-easy/RAML) uses YAML::Syck which uses libsyck which is compatible with YAML 1.1.

In reply to Re: Are we lacking behind in YAML spec versions? by mikkoi
in thread Are we lacking behind in YAML spec versions? by mikkoi

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