nomsu/parser.lua
Bruce Hill 86a3219e7f Cleanup of some metaprogramming stuff, as well as adding support for
"package.nomsupath" to search for files in different locations, and
prioritizing use of "luafilesystem" over system calls.
2018-06-21 19:13:47 -07:00

170 lines
6.0 KiB
Lua

local lpeg = require('lpeg')
local re = require('re')
lpeg.setmaxstack(10000)
local P, R, V, S, Cg, C, Cp, B, Cmt, Carg
P, R, V, S, Cg, C, Cp, B, Cmt, Carg = lpeg.P, lpeg.R, lpeg.V, lpeg.S, lpeg.Cg, lpeg.C, lpeg.Cp, lpeg.B, lpeg.Cmt, lpeg.Carg
local utils = require('utils')
local match, sub, rep, gsub, format, byte, find
do
local _obj_0 = string
match, sub, rep, gsub, format, byte, match, find = _obj_0.match, _obj_0.sub, _obj_0.rep, _obj_0.gsub, _obj_0.format, _obj_0.byte, _obj_0.match, _obj_0.find
end
local NomsuCode, LuaCode, Source
do
local _obj_0 = require("code_obj")
NomsuCode, LuaCode, Source = _obj_0.NomsuCode, _obj_0.LuaCode, _obj_0.Source
end
local AST = require("nomsu_tree")
local NOMSU_DEFS
do
local _with_0 = { }
_with_0.nl = P("\r") ^ -1 * P("\n")
_with_0.ws = S(" \t")
_with_0.tonumber = tonumber
local string_escapes = {
n = "\n",
t = "\t",
b = "\b",
a = "\a",
v = "\v",
f = "\f",
r = "\r"
}
local digit, hex = R('09'), R('09', 'af', 'AF')
_with_0.escaped_char = (P("\\") * S("xX") * C(hex * hex)) / function(self)
return string.char(tonumber(self, 16))
end
_with_0.escaped_char = _with_0.escaped_char + ((P("\\") * C(digit * (digit ^ -2))) / function(self)
return string.char(tonumber(self))
end)
_with_0.escaped_char = _with_0.escaped_char + ((P("\\") * C(S("ntbavfr"))) / string_escapes)
_with_0.operator_char = S("'`~!@$^&*-+=|<>?/")
_with_0.utf8_char = (R("\194\223") * R("\128\191") + R("\224\239") * R("\128\191") * R("\128\191") + R("\240\244") * R("\128\191") * R("\128\191") * R("\128\191"))
_with_0.ident_char = R("az", "AZ", "09") + P("_") + _with_0.utf8_char
_with_0.indent = Cmt(Carg(1), function(self, start, userdata)
local indented = userdata.indent .. ' '
if sub(self, start, start + #indented - 1) == indented then
userdata.indent = indented
return start + #indented
end
end)
_with_0.dedent = Cmt(Carg(1), function(self, start, userdata)
local dedented = sub(userdata.indent, 1, -5)
if #match(self, "^[ ]*", start) <= #dedented then
userdata.indent = dedented
return start
end
end)
_with_0.nodent = Cmt(Carg(1), function(self, start, userdata)
if sub(self, start, start + #userdata.indent - 1) == userdata.indent then
return start + #userdata.indent
end
end)
_with_0.userdata = Carg(1)
_with_0.error = function(src, end_pos, start_pos, err_msg, userdata)
local seen_errors = userdata.errors
if seen_errors[start_pos] then
return true
end
if utils.size(seen_errors) >= 10 then
seen_errors[start_pos + 1] = colored.bright(colored.yellow(colored.onred("Too many errors, canceling parsing...")))
return #src + 1
end
local err_pos = start_pos
local line_no = pos_to_line(src, err_pos)
src = FILE_CACHE[userdata.source.filename]
local line_starts = LINE_STARTS[src]
local prev_line = line_no == 1 and "" or src:sub(line_starts[line_no - 1] or 1, line_starts[line_no] - 2)
local err_line = src:sub(line_starts[line_no], (line_starts[line_no + 1] or 0) - 2)
local next_line = src:sub(line_starts[line_no + 1] or -1, (line_starts[line_no + 2] or 0) - 2)
local i = err_pos - line_starts[line_no]
local pointer = ("-"):rep(i) .. "^"
err_msg = colored.bright(colored.yellow(colored.onred((err_msg or "Parse error") .. " at " .. tostring(userdata.source.filename) .. ":" .. tostring(line_no) .. ":")))
if #prev_line > 0 then
err_msg = err_msg .. ("\n" .. colored.dim(prev_line))
end
err_line = colored.white(err_line:sub(1, i)) .. colored.bright(colored.red(err_line:sub(i + 1, i + 1))) .. colored.dim(err_line:sub(i + 2, -1))
err_msg = err_msg .. "\n" .. tostring(err_line) .. "\n" .. tostring(colored.red(pointer))
if #next_line > 0 then
err_msg = err_msg .. ("\n" .. colored.dim(next_line))
end
seen_errors[start_pos] = err_msg
return true
end
NOMSU_DEFS = _with_0
end
setmetatable(NOMSU_DEFS, {
__index = function(self, key)
local make_node
make_node = function(start, value, stop, userdata)
if userdata.source then
do
local _with_0 = userdata.source
value.source = Source(_with_0.filename, _with_0.start + start - 1, _with_0.start + stop - 1)
end
end
setmetatable(value, AST[key])
if value.__init then
value:__init()
end
for i = 1, #value do
assert(value[i])
end
return value
end
self[key] = make_node
return make_node
end
})
local NOMSU_PATTERN
do
local peg_tidier = re.compile([[ file <- {~ %nl* (def/comment) (%nl+ (def/comment))* %nl* ~}
def <- anon_def / captured_def
anon_def <- ({ident} (" "*) ":"
{((%nl " "+ [^%nl]*)+) / ([^%nl]*)}) -> "%1 <- %2"
captured_def <- ({ident} (" "*) "(" {ident} ")" (" "*) ":"
{((%nl " "+ [^%nl]*)+) / ([^%nl]*)}) -> "%1 <- (({} %3 {} %%userdata) -> %2)"
ident <- [a-zA-Z_][a-zA-Z0-9_]*
comment <- "--" [^%nl]*
]])
local nomsu_peg = peg_tidier:match(io.open((package.nomsupath or '.') .. "/nomsu.peg"):read('*a'))
NOMSU_PATTERN = re.compile(nomsu_peg, NOMSU_DEFS)
end
local parse
parse = function(nomsu_code, source)
if source == nil then
source = nil
end
nomsu_code = tostring(nomsu_code)
local userdata = {
indent = "",
errors = { },
source = source
}
local tree = NOMSU_PATTERN:match(nomsu_code, nil, userdata)
if not (tree) then
error("In file " .. tostring(colored.blue(tostring(source or "<unknown>"))) .. " failed to parse:\n" .. tostring(colored.onyellow(colored.black(nomsu_code))))
end
if type(tree) == 'number' then
tree = nil
end
if next(userdata.errors) then
local keys = utils.keys(userdata.errors)
table.sort(keys)
local errors
do
local _accum_0 = { }
local _len_0 = 1
for _index_0 = 1, #keys do
local k = keys[_index_0]
_accum_0[_len_0] = userdata.errors[k]
_len_0 = _len_0 + 1
end
errors = _accum_0
end
error("Errors occurred while parsing:\n\n" .. table.concat(errors, "\n\n"), 0)
end
return tree
end
return parse