unifiedjs/unified

unify AST types

milahu opened this issue · 1 comments

milahu commented

Initial checklist

Problem

xast-parse produces a different AST than hast-parse
so i cannot use hast-util-select on xast

part of rehypejs/rehype#112 (trying to use hast tools for xml)

Solution

unify ASTs across all parsers in the unifiedjs ecosystem
so that tools like select "just work" on all ASTs

interface Node {
  name: string,
  type: string,
  props: Record<string, any> | null,
  children: Node[] | null, // node is a branch node
  value: string?, // node is a leaf node
  location: { start: number, end: number },
  internal: Record<string, any> | null, // like props, but for unifiedjs internal data
  // example: path to source file of a root node
  isRoot: boolean, // shortcut to detect "context switch" between different ASTs
}

this would also allow to just "plug in" tools like graphQL, or interface with graph databases ...

benefit: ASTs are composable, for example, i can embed a python AST in a html code block.
or, i can parse <img src="image.svg">, parse the svg file at src, transform the svg, inline the svg in html

maybe extend the Node type of a parser-generator like tree-sitter or lezer-parser

Alternatives

write N tools for M ASTs ...

which is the opposite of "unified"

"what would pandoc do?"

wooorm commented

Please respect our time by filling out the template, following the support guidelines, and taking some time to think through your questions. I will block you otherwise.

You can use unist-util-select in any unist language.
unified is specifically not pandoc, it specifically has different ASTs, being like Pandoc is not the goal. Pandoc is already a very good version of Pandoc.

  • 👍3