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Comment by coldtea | Hacker News Reader

What's with this childish "can you prove this, can you prove that" thing? Are you 12 year old?

Not everything can (or should) be proved of the drop of a hat in a discussion list -- that doesn't make everything without a formal proof "baseless" opinion.

If you cannot see the self-evidentness (sic) of a STRUCTURED API to produce an AST makes it easier to avoid mistakes compared to spitting out text to compile as a C program, then I'm not sure any proof would help anyway.

It's like asking me to prove why using an XML processor to crete and save a DOM tree would produce more error free results than manually compiling tags as strings.

Or why parsing a JSON file and working on the nodes is less error prone than using regular expressions to extract values from the JSON as a big string.

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  Not everything can (or should) be proved of the drop 
  of a hat in a discussion list

If you say something that doesn't make sense, you're saying that one shouldn't have to back that up?

  It's like asking me to prove why using an XML processor 
  to crete and save a DOM tree would produce more error 
  free results than manually compiling tags as strings.

It is in fact the equivalent of asking you to prove that an XML parser after serializing a DOM tree and then parsing that same document produces a non-equivalent DOM tree to the original.

I think the reason pat_punnu is balking at what you have said is because of this: You can think of C as a serialized form of an AST. In order for parsing to produce a non-equivalent AST to the one used to serialize it, the C grammar must be non-deterministic. The C grammar is not non-deterministic, therefore what you said does not make sense and pat_punnu (somewhat rudely) asked you to back up what you were saying.

Asking people to back up what they have claimed is part of intelligent discourse. This happens often on HN and is one of the reasons I like this community because when the person who makes a non-intuitive or seemingly wrong remark turns out to be correct, I learn something.

UPDATE: I should point out that I'm responding specifically to this sub-thread of the tree and not arguing about whether or not this should target the LLVM IR. I think that would be nice.

>>Not everything can (or should) be proved of the drop of a hat in a discussion list >If you say something that doesn't make sense, you're saying that one shouldn't have to back that up?

Read what you quoted from me, and what you ask. Where do I say that people should not back up things they say that "don't make sense"?

Where do I even say they do not have to "back up" the things they say? I merely say that they do not have to PROVE everything. You can back stuff up with some arguments and counterargurments, you don't need to provide some "proof".

>I think the reason pat_punnu is balking at what you have said is because of this: You can think of C as a serialized form of an AST. In order for parsing to produce a non-equivalent AST to the one used to serialize it, the C grammar must be non-deterministic. The C grammar is not non-deterministic, therefore what you said does not make sense and pat_punnu (somewhat rudely) asked you to back up what you were saying.

And the reason I'm balking at this is that you examine the case AFTER C has been generated. I'm not talking about that stage (when reading back C to generate an AST). I (and pat_punnu) and talking at the previous stage of spitting out the C code to disk in the first place. I'm saying that a structured way to do that (LLVM API) is safer than merely creating strings yourself.

So your: "It is in fact the equivalent of asking you to prove that an XML parser after serializing a DOM tree and then parsing that same document produces a non-equivalent DOM tree to the original"

takes this from several steps ahead. I (and pat_punny) were concerned with the generation of the document in the first place.

> I'm saying that a structured way to do that (LLVM API) is safer than merely creating strings yourself.

That is resting on the assumption that using the LLVM API is less error prone to a typical compiler developer than creating strings.

You are also assuming that spitting the C code to disk needs to be done in an unstructured way.

Neither of these assumptions are self evident.

We work in a technical field. We call ourselves engineers. The academic version is computer SCIENCE. Unsupportable opinions and opinions presented as facts are inexcusable.

Can you prove that? If not, it's just a baseless opinion.

Isn't that just a charming response to get?

>Unsupportable opinions and opinions presented as facts are inexcusable.

I don't see any proof fot that. Where's your proof?

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