The ParseJS stringifier does not guarantee equivalent whitespace and comments in a round-trip, but it should guarantee semantic equivalence.
The ParseJS parser maintains comments in most cases where comments would represent inline documentation.
- top-level statement: a ParseJS top-level statement node contains any comment that immediately preceded it.
- property: in a property list (object literal), a property node contains any comment that immediately preceded it.
ParseJS is provided as a Rubygem. At the moment, you can use it in your Gemfile by using Bundler's git feature.
gem "parsejs", :git => "git://github.com/wycats/parsejs.git"
ast = ParseJS.parse(some_data)
You can write your own AST walker without implementing visitors for all
nodes by subclassing
ParseJS::Visitor. Take a look
at that class
to see the default visitor behavior for a particular node.
By default, nodes
accept their children. Nodes that have children that
Arrays of nodes (e.g.
FunctionDeclaration, which has an
parameters and an
Array of statements as children) default to looping
Arrays and accepting their members.
Copyright (C) 2012 Yehuda Katz
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