Voila, now your 'string' is 'binary data' not 'text'.

Parsing binary data is my bread and butter, so I might be biased but: it works fine.

Anything which comes over the wire is a string, anything which comes out of store is a string. If you're using something like protobufs, that's great, because having to marshal/serialize/parse along every process boundary is expensive and probably unnecessary.

But at some point, and anywhere on the 'surface' of the system, data has to be un-flattened into a shape. That's parsing.

Ha yeah nice catch, that's why I added that in there. In this case the dictionary is slightly wrong.

> The defining aspect of parsing, that makes it difficult and an interesting thing to study, is that you're starting with a list and ending with a tree.

Ah, I didn't know that! Great bit to learn.

In that case, I will say that the "increase a data structure's rules" is a bit ambiguous.

I think my statement is still correct in that "a symbol could be a data structure," right? Like you could take a list of dicts and emit a tree of dicts.

But wait, a list is a kind of tree, or rather, there is a parse tree of recursive head/tail branches. So I think you could still argue List->NotEmptyList is a Parse because NEL requires a nonzero "head" and zero or one NEL as "tail."