From: eregontp@... Date: 2019-04-07T19:07:14+00:00 Subject: [ruby-core:92185] [Ruby trunk Feature#14844] Future of RubyVM::AST? Issue #14844 has been updated by Eregon (Benoit Daloze). mame (Yusuke Endoh) wrote: > As far as I understand, RubyVM module is completely different than other builtin modules. > It exposes an access to Ruby internal for very limited purpose, such as debugging the internal, prototyping a new feature, implementing a MRI-bundled feature, etc. No compatibility is guaranteed at all; its API will arbitrarily change along with internal change. It is never intended for normal users to use it. Usefulness is not a priority for the modules under RubyVM. > > `RubyVM::AST` does not decrease the value of the parser gem. `RubyVM::AST` is useful to investigate how MRI looks a Ruby program, but is not useful as a general Ruby program parser; it may optimize the AST by omitting some non-significant letters and restructuring the tree structure, so the result might not correspond to the original source code literally. > > In short, I think that RubyVM::AST is not what people expected. > Users may use it just for research purpose, but must not use it in production. @mame Could you summarize this in the documentation of `RubyVM::AbstractSyntaxTree`? Currently, it doesn't mention anything about being not stable, being not so appropriate for source code analysis, etc: ``` AbstractSyntaxTree provides methods to parse Ruby code into abstract syntax trees. The nodes in the tree are instances of RubyVM::AbstractSyntaxTree::Node. ``` --- I think that such an AST module could have the potential to be portable, but it would need to be much more fledged out. Relying on the order of `children` to access AST node fields is impractical and brittle. I think we should have nodes with methods to access each part/field, such as ModuleDefinitionNode#body, ModuleDefinitionNode#name, etc. ---------------------------------------- Feature #14844: Future of RubyVM::AST? https://bugs.ruby-lang.org/issues/14844#change-77514 * Author: rmosolgo (Robert Mosolgo) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- Hi! Thanks for all your great work on the Ruby language. I saw the new RubyVM::AST module in 2.6.0-preview2 and I quickly went to try it out. I'd love to have a well-documented, user-friendly way to parse and manipulate Ruby code using the Ruby standard library, so I'm pretty excited to try it out. (I've been trying to learn Ripper recently, too: https://ripper-preview.herokuapp.com/, https://rmosolgo.github.io/ripper_events/ .) Based on my exploration, I opened a small PR on GitHub with some documentation: https://github.com/ruby/ruby/pull/1888 I'm curious though, are there future plans for this module? For example, we might: - Add more details about each node (for example, we could expose the names of identifiers and operators through the node classes) - Document each node type I see there is a lot more information in the C structures that we could expose, and I'm interested to help out if it's valuable. What do you think? -- https://bugs.ruby-lang.org/ Unsubscribe: