kdl/CHANGELOG.md

KDL Changelog

2.0.0 (2022-08-28)

Grammar

• Solidus/Forward slash (/) is no longer an escaped character.
• Single line comments (//) can now be immediately followed by a newline.
• All literal whitespace following a \ in a string is now discarded.
• Vertical tabs (U+000B) are now considered to be whitespace.
• Identifiers can't start with r#, so they're easy to distinguish from raw strings. (They already similarly can't start with a digit, or a sign+digit, so they're easy to distinguish from numbers.)
• The grammar syntax itself has been described, and some confusing definitions in the grammar have been fixed accordingly (mostly related to escaped characters).
• ,, <, and > are now legal identifier characters. They were previously reserved for KQL but this is no longer necessary.
• Code points under 0x20, code points above 0x10FFFF, Delete control character (0x7F), and the unicode "direction control" characters are now completely banned from appearing literally in KDL documents. They can now only be represented in regular strings, and there's no facilities to represent them in raw strings. This should be considered a security improvement.

KQL

• There's now a required descendant selector (>>), instead of using plain spaces for that purpose.
• The "any sibling" selector is now ++ instead of ~, for consistency with the new descendant selector.
• Map operators have been removed entirely.