Update JSON package to version 0.4

[d-torrance]

We export remove the JSONEncoder class so that developers can write their own toJSON methods. Thanks @mahrud for the suggestion!

[mahrud]

Also, take a look at various json methods I had to define to deal with serializing hypertext objects and documentation nodes here. I had to resort to a hacky middle ground which you might not like, namely having toJSON VisibleList return an Array and toJSON HashTable return a HashTable, then writing format' to convert to a string. This was necessary to handle nested hash tables and lists without superfluous quotations all over the place, but perhaps there is an easier solution that I missed.

I don't remember the reason for each particular entry, but once you have toJSON Hypertext, as a challenge try something like this with different packages:

elapsedTime pkg = loadPackage(pkgname, Reload => true, LoadDocumentation => true)

L = new HashTable from pkg#"raw documentation";
L = selectValues(L, x -> not x#?PrimaryTag and not x#?"undocumented");
elapsedTime ("static/"|pkgname|".json") << toJSON(L, Indent => 2) << flush << close

I still can't get Macaulay2Doc serialized this way, but smaller packages work fine.

[d-torrance]

Cool, I'll check it out!

[mahrud]

This is not valid JSON:

i14 : json { "A\nB" }

o14 = ["A
      B"]

i15 : fromJSON json { "A\nB" }
stdio:16:8:(3): error: syntax error at token '
', position 3

[d-torrance]

I added a few new toJSON methods so that calling toJSON on a package's raw documentation appears to mostly work.

[d-torrance]

This is not valid JSON:

Indeed! Good catch.

[mahrud]

I added a few new toJSON methods so that calling toJSON on a package's raw documentation appears to mostly work.

Now try fromJSON and compare with the raw documentation haha

[mahrud]

I think other than the newline issue this is working great.

An annoying source of complexity for me was if I want json TO to print links in a different way, then I also need to reimplement json SPAN and any other container which may contain a TO. The shortcut is to just redefine html TO, but that would have other side-effects that break the rest of the system. I'm not sure how to handle this best.

[mahrud]

This is mostly unrelated, but do you know what's happening here?

i35 : html Saturation#"raw documentation"#"annihilator"#Inputs#0

o35 = <span><span class="tt">M</span>, $\left\{\texttt{an }\texttt{DocumentTag}\left\{\mathit{Format}\ \Rightarrow \
      \texttt{Ideal},\:\mathit{Key}\ \Rightarrow \ \mathit{Ideal},\:\mathit{Package}\ \Rightarrow \
      \texttt{Macaulay2Doc},\:\texttt{RawDocumentation}\ \Rightarrow \ \texttt{null}\right\}\texttt{ideal},\:\texttt{,
      },\:\texttt{a }\texttt{DocumentTag}\left\{\mathit{Format}\ \Rightarrow \ \texttt{Module},\:\mathit{Key}\ \Rightarrow \
      \mathit{Module},\:\mathit{Package}\ \Rightarrow \ \texttt{Macaulay2Doc},\:\texttt{RawDocumentation}\ \Rightarrow \
      \texttt{null}\right\}\texttt{module},\:\texttt{, or },\:\texttt{a }\texttt{DocumentTag}\left\{\mathit{Format}\
      \Rightarrow \ \texttt{RingElement},\:\mathit{Key}\ \Rightarrow \ \mathit{RingElement},\:\mathit{Package}\ \Rightarrow \
      \texttt{Macaulay2Doc},\:\texttt{RawDocumentation}\ \Rightarrow \ \texttt{null}\right\}\texttt{ring element}\right\}$,
      </span>

[d-torrance]

Maybe this is overkill, but I went ahead and updated format so that it escapes newline characters (plus a few others -- all the ones we can escape in M2 strings). This seems like reasonable behavior based on its documentation:

a string obtained from s by inserting escape sequences, thereby preparing it for printing in a form suitable for reading in again

It's still not quite right when composing with fromJSON, though:

i2 : fromJSON toJSON "foo\nbar"

o2 = foo\nbar

i3 : oo == "foo\nbar"

o3 = false