Documentation

The options of renderSyntax.

Keep the collection styles of the tree.

Render documents with their comments and empty lines.

The output differs from the tree where YAML cannot hold it:

• A --- marker is on a line of its own, with at most a comment after it.
• A scalar keeps its style if the style can hold its text, otherwise it gets quotes. A block scalar that is a key or an entry of a flow collection gets double quotes. A block scalar at the root gets quotes in a few more cases, e.g. if its text starts with a space.
• The empty lines from the comments right after a block scalar with the + indicator go away, because they would become part of the scalar.
• A flow collection with comments inside becomes a block collection, so that every comment has a line.
• A flow collection without comments is on one line, apart from the line breaks of its multi-line scalars, so the empty lines between its entries go away.
• A key of more than 1024 characters in a flow mapping becomes an explicit key, e.g. {? key : value}, because YAML 1.1 parsers reject a longer implicit key there too.
• A comment that has no place at its node moves to a place that has one, e.g. the lines above the value of a key go above the key if the value is on the line of the key.
• In the text of a comment, a character that YAML does not allow becomes U+FFFD, and the white space at the end goes away. A line break starts a new comment in a CommentLine, and becomes a space in an inline comment.
• An anchor name with a character that YAML does not allow in it, e.g. a space, or that YAML 1.1 parsers read as the end of the name, e.g. : or a line separator, becomes a new name in the anchor and in its aliases. Names that only some parsers reject stay, e.g. é, which libyaml rejects.
• A version that the parser does not support, e.g. 2.0, has no %YAML directive.

With forceBlock, the flow collections become block collections:

>>> :{
case parseDocumentsText "a: [1, {b: 2}]\n" of
  Left err -> putStrLn (prettyError "input.yaml" err)
  Right docs ->
    T.putStr (renderSyntax defaultRenderOptions {forceBlock = True} docs)
:}
a:
- 1
- b: 2