beginning work on autogenerated docs

so that lua5.1 through lua5.4 will have accurate docs. There are *so*
many minor changes between the versions that I don't trust myself to
manually audit the differences. Also, if they release a lua 5.5 I do
not want to bother with it.

make-docs.fnl

@@ -0,0 +1,61 @@
+"work in progress script to generate /src/fennel-ls/docs/lua54.fnl automatically"
+
+(local version "5.4")
+(local filename (.. "lua" version ".html"))
+(var file (io.open filename :r))
+(when (not file)
+  ;; I think the repos also have the html file (or the ability to generate it, depending on lua version)
+  ;; but for simplicity I'm just grabbing the html straight from the website
+  (os.execute (.. "curl https://www.lua.org/manual/" version "/manual.html > lua" version ".html"))
+  (set file (io.open filename :r)))
+
+(local html (file:read :a))
+
+;; The section about the standard library
+(local begin-index (assert (html:find "<h2>.%.1 &ndash; <a name=\".%.1\">Basic Functions.-\n")))
+(local end-index (assert (html:find "<h1>. &ndash; <a name=\".\".-\n" begin-index)))
+(local stdlib (html:sub begin-index (- end-index 1)))
+
+
+;; Each section split by <h3>
+;; TODO figure out <h2>
+(local sections [])
+(fn loop [prev]
+  (let [header (stdlib:find "<hr><h3>.-\n" (+ prev 1))
+        section (stdlib:sub prev (if header (- header 1)))]
+    (table.insert sections section)
+    (when header (loop header))))
+(loop (stdlib:find "<hr><h3>.-\n"))
+
+;; I should probably split more of this file into functions like this
+(fn process-html-thing [html-describing-the-thing]
+  (let [(header description) (html-describing-the-thing:match "^(.-)\n+(.-)\n*$")
+        optional-args []
+        signature (header:match "<code>(.-)</code>")
+        ;; Replace `[]`'d args with ?-prefixes
+        ;; Three times is enough, as `table.concat` and `load` and `loadfile`
+        ;; and `utf8.codepoint` and `utf8.len` have 3 sets of []'s.
+        ;; Lua 5.2 manual has a typo, so the last pass makes the `]` optional.
+        signature (signature:gsub "%[,? ?([^%[%] ]+)([^%[%]]-)%](%]-%))"
+                                  #(do (table.insert optional-args $1) (.. :? $1 $2 $3)))
+        signature (signature:gsub "%[,? ?([^%[%] ]+)([^%[%]]-)%](%]-%))"
+                                  #(do (table.insert optional-args $1) (.. :? $1 $2 $3)))
+        signature (signature:gsub "%[,? ?([^%[%] ]+)([^%[%]]-)%]?(%]-)%)"
+                                  #(do (table.insert optional-args $1) (.. :? $1 $2 $3)))
+        ;; For some reason, they use an html middot, but we want to use periods.
+        signature (signature:gsub "&middot;&middot;&middot;" "...")]
+    nil
+    ;; Debug prints for now. I'm not sure how to process the description.
+    (if (not (signature:match "%("))
+      ;; (print "c" signature)
+      nil
+      (and (signature:match "[%[]")
+           (not (signature:match "debug"))
+           (not (signature:match "table.insert")))
+      (do
+        (print "========================" signature))
+      (print "?" signature))))
+
+
+(each [_ section (ipairs sections)]
+  (process-html-thing section))