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For those curious about how this would deal with Function.prototype.toSource, via https://github.com/syg/ecmascript-binary-ast#functionprototypetostring https:/

For those curious about how this would deal with Function.prototype.toSource, via https://github.com/syg/ecmascript-binary-ast#functionprototypetostring https://github.com/syg/ecmascript-binary-ast#functionprototy...: > This method would return something like "[sourceless code]".

_wmd 9y ago
It seems this would break a number of libraries (can't name one, but certain I've seen it), although per the article it would be a simple affair for the browser to reify the encoded AST into a compatible representation, especially if comments are also eventually preserved (per article its on the roadmap)
- Yoric 9y ago
  It would be interesting to find any library that actually depends on that. There used to be some, but I haven't seen any in years. If you do find one, please feel free to add a comment on the blog or one of the trackers :)
  - mnarayan01 9y ago
    I remember reading about some framework which was doing something nutty like embedding actual data in the comments on a function, and then parsing out those comments at run-time. For what it's worth, I believe it was on HN and in relation to the caveats for older V8 optimization w.r.t. function length (https://top.fse.guru/nodejs-a-quick-optimization-advice-7353b820c92e https://top.fse.guru/nodejs-a-quick-optimization-advice-7353...), but it was years ago so, as you say, hopefully they moved to something less insane in the intervening time. Aside since you're here. The "Would it be possible to write a tool to convert serialized AST back to JS?" portion of the FAQ (https://github.com/syg/ecmascript-binary-ast#faq https://github.com/syg/ecmascript-binary-ast#faq) says that it would be possible to generate source which would be "semantically equivalent" -- you might want to call out the Function.prototype.toString exception explicitly there, though admittedly that level of pedantry might be more obscuring than enlightening.

_wmd 9y ago

It seems this would break a number of libraries (can't name one, but certain I've seen it), although per the article it would be a simple affair for the browser to reify the encoded AST into a compatible representation, especially if comments are also eventually preserved (per article its on the roadmap)

Yoric 9y ago
It would be interesting to find any library that actually depends on that. There used to be some, but I haven't seen any in years. If you do find one, please feel free to add a comment on the blog or one of the trackers :)
- mnarayan01 9y ago
  I remember reading about some framework which was doing something nutty like embedding actual data in the comments on a function, and then parsing out those comments at run-time. For what it's worth, I believe it was on HN and in relation to the caveats for older V8 optimization w.r.t. function length (https://top.fse.guru/nodejs-a-quick-optimization-advice-7353b820c92e https://top.fse.guru/nodejs-a-quick-optimization-advice-7353...), but it was years ago so, as you say, hopefully they moved to something less insane in the intervening time. Aside since you're here. The "Would it be possible to write a tool to convert serialized AST back to JS?" portion of the FAQ (https://github.com/syg/ecmascript-binary-ast#faq https://github.com/syg/ecmascript-binary-ast#faq) says that it would be possible to generate source which would be "semantically equivalent" -- you might want to call out the Function.prototype.toString exception explicitly there, though admittedly that level of pedantry might be more obscuring than enlightening.