1501541 - [BinAST] Function's displayName algorithm depends on the existence of parenthesis, which cannot be represented in current BinAST spec

Status: RESOLVED WONTFIX

(Core :: JavaScript Engine, enhancement, P3)

Description

[Tooru Fujisawa [:arai]]

code:

var Foo = function (){
    return function(){};
}();
print(displayName(Foo));


the result with plain JS
  Foo</<

the result with BinAST
  Foo

Comment 1

[Tooru Fujisawa [:arai]]

looks like something related to eager/lazy compilation.

code:
  var Foo = (function (){
      return function(){};
  })();
  print(displayName(Foo));



the result with plain JS
  Foo

the result with BinAST
  Foo

Comment 2

[Tooru Fujisawa [:arai]]

This depends on the spec, which currently doesn't support have interface for parenthesis.
(and also the JS parser in binjs-ref)

We should think about whether it makes sense to introduce parenthesis interface into the AST or not.

Some parenthesis are already implicitly represented in the AST, because of operator precedence,
but redundant parenthesis are just omitted.

Representing all parenthesis in the AST will make the file bigger, and also decode longer.

Introducing only redundant parenthesis will be nice to keep the AST small, but encoder (and possibly decoder) will become complicated.