Proposal to remove single-line comments

[lsloan]

When JSON5 data includes single-line comments, if the data is compacted by removing whitespace, any data that follows the comments may appear to be a comment as well. To prevent that, multiline comments could always be used, because the end of comments will be explicit. Single-line comment support could be phased out to prevent problems caused by compacting data.

[jordanbtucker]

Thanks for the suggestion. Rather than removing single line comments from JSON5, I think it should be the minifier's responsibility to convert single line comments to multiline comments or just remove comments completely.

// Unminified
{
  // This comment documents this property.
  message: 'Don\'t forget to pick up eggs.',
}

// Minified with comments
{/* This comment documents this property.*/message:"Don't forget to pick up eggs."}

// Minified without comments
{message:"Don't forget to pick up eggs."}

[lsloan]

I guess that's not unreasonable. It makes the minifier's job a little more complex than just removing whitespace.

[jordanbtucker]

Since the goal of a minifier is to make the payload as small as possible, this would likely include removing comments, but would also include more optimizations.

• 912559 is one character fewer than 0xDECAF.
• "Don't forget to pick up eggs." is one character fewer than 'Don\'t forget to pick up eggs.'.
• 1 is four characters fewer than 1.000.
• {abc:123} is three characters fewer than {'abc': 123}.

The easiest way to do this is to just round-trip the JSON5 document since JSON5 usually outputs the most efficient version by default.

const json5 = `
{
  // This comment documents this property.
  "message": 'Don\\'t forget to pick up eggs.',
  "hex": 0xDECAF,
  "dec": 123.000,
}
`

const minified = JSON5.stringify(JSON5.parse(json5))

console.log(minified) // {message:"Don't forget to pick up eggs.",hex:912559,dec:123}

Some minifiers have an option to preserve documentation comments, which are usually in the form /** Documentation goes here. */, which is a multi-line comment anyway.