if not parser then

load_parser()

end

if round == 1 then

return filename:match(".sil$")

elseif round == 2 then

local sniff = doc:sub(1, 100)

local promising = sniff:match("\\begin") or sniff:match("\\document") or sniff:match("\\sile")

return promising and inputter.appropriate(3, filename, doc) or false

elseif round == 3 then

local status, _ = pcall(parser, doc)

return status

end

options = options or {}

if options.variant then

_variant = options.variant

load_parser()

else

if not parser then

load_parser()

end

end

-- Save time when parsing strings by only setting up the grammar once per

-- instantiation then re-using it on every use.

self._parser = parser

base._init(self)

lno = 1

col = 1

lastpos = 0

linecache = { { lno = 1, pos = 1 } }

local start = 1

lno = 1

if pos > lastpos then

lno = linecache[#linecache].lno

start = linecache[#linecache].pos 1

col = 1

else

for j = 1, #linecache - 1 do

if linecache[j 1].pos >= pos then

lno = linecache[j].lno

col = pos - linecache[j].pos

return lno, col

end

end

end

for i = start, pos do

if string.sub(str, i, i) == "\n" then

lno = lno 1

col = 1

linecache[#linecache 1] = { pos = i, lno = lno }

lastpos = i

end

col = col 1

end

return lno, col

if type(tree) == "string" then

return tree

end

if tree.pos then

tree.lno, tree.col = getline(doc, tree.pos)

tree.pos = nil

end

local sep -- luacheck: ignore 211

if SU.debugging("inputter") then

depth = depth 1

sep = (" "):rep(depth)

end

SU.debug("inputter", sep and (sep .. "Processing ID:"), tree.id)

local res

if tree.id == "comment" then

-- Drop comments

SU.debug("inputter", sep and (sep .. "Discarding comment"))

res = {}

elseif

false

or tree.id == "document"

or tree.id == "braced_content"

or tree.id == "passthrough_content"

or tree.id == "braced_passthrough_content"

or tree.id == "env_passthrough_content"

or tree.id == "text"

or tree.id == "passthrough_text"

or tree.id == "braced_passthrough_text"

or tree.id == "env_passthrough_text"

then

-- These nodes have only one child, which needs recursion.

SU.debug("inputter", sep and (sep .. "Massaging a node"))

res = ast_from_parse_tree(tree[1], doc, depth)

--res = #res > 1 and not res.id and res or res[1]

elseif false or tree.id == "environment" or tree.id == "command" then

-- These nodes have multiple children, which need recursion.

SU.debug("inputter", sep and (sep .. "Processing command"), tree.command, #tree, "subtrees")

local newtree = { -- I don't think we can avoid a shallow copy here

command = tree.command,

options = tree.options,

id = tree.id,

lno = tree.lno,

col = tree.col,

}

for _, node in ipairs(tree) do

if type(node) == "table" then

SU.debug("inputter", sep and (sep .. " -"), node.id or "table")

local ast_node = ast_from_parse_tree(node, doc, depth)

if type(ast_node) == "table" and not ast_node.id then

SU.debug("inputter", sep and (sep .. " -"), "Collapsing subtree")

-- Comments can an empty table, skip them

if #ast_node > 0 then

-- Simplify the tree if it's just a plain list

for _, child in ipairs(ast_node) do

if type(child) ~= "table" or child.id or #child > 0 then

table.insert(newtree, child)

end

end

end

else

table.insert(newtree, ast_node)

end

end

-- Non table nodes are skipped (e.g. extraneous text from 'raw' commands)

end

res = newtree

elseif tree.id == "content" then

-- This node has multiple children, which need recursion

-- And the node itself needs to be replaced with its children

SU.debug("inputter", sep and (sep .. "Massage content node"), #tree, "subtrees")

local newtree = {} -- I don't think we can avoid a shallow copy here

for i, node in ipairs(tree) do

SU.debug("inputter", sep and (sep .. " -"), node.id)

newtree[i] = ast_from_parse_tree(node, doc, depth)

end

-- Simplify the tree if it has only one child

res = #newtree == 1 and not newtree.id and newtree[1] or newtree

elseif tree.id then

-- Shouldn't happen, or we missed something

SU.error("Unknown node type: " .. tree.id)

else

SU.debug("inputter", sep and (sep .. "Table node"), #tree, "subtrees")

res = #tree == 1 and tree[1] or tree

end

SU.debug("inputter", sep and (sep .. "Returning a"), type(res) == "table" and res.id or "string")

return res

local status, result = pcall(self._parser, doc)

if not status then

return SU.error(([[

Unable to parse input document to an AST tree

Parser error:

%s

thrown from document beginning.]]):format(pl.stringx.indent(result, 6)))

end

resetCache()

local top = ast_from_parse_tree(result[1], doc, 0)

local tree

-- Content not part of a tagged command could either be part of a document

-- fragment or junk (e.g. comments, whitespace) outside of a document tag. We

-- need to either capture the document tag only or decide this is a fragment

-- and wrap it in a document tag.

if top.command == "document" or top.command == "sile" then

tree = top

elseif type(top) == "table" then

for _, leaf in ipairs(top) do

if leaf.command and (leaf.command == "document" or leaf.command == "sile") then

tree = leaf

break

end

end

end

-- In the event we didn't isolate a top level document tag above, assume this

-- is a fragment and wrap it in one.

if not tree then

tree = { top, command = "document" }

end

return { tree }