alunizaje/StartGamedev-160604-osx/tools/zbstudio.app/Contents/ZeroBraneStudio/lualibs/lua_lexer_loose.lua

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2016-11-03 00:05:36 +01:00
--[[
lua_lexer_loose.lua.
Loose lexing of Lua code. See README.
WARNING: This code is preliminary and may have errors
in its current form.
(c) 2013 David Manura. MIT License.
--]]
local M = {}
-- based on LuaBalanced
local function match_string(s, pos)
pos = pos or 1
local posa = pos
local c = s:sub(pos,pos)
if c == '"' or c == "'" then
pos = pos + 1
while 1 do
pos = s:find("[" .. c .. "\\]", pos)
if not pos then return s:sub(posa), #s + 1 end -- not terminated string
if s:sub(pos,pos) == c then
local part = s:sub(posa, pos)
return part, pos + 1
else
pos = pos + 2
end
end
else
local sc = s:match("^%[(=*)%[", pos)
if sc then
local _; _, pos = s:find("%]" .. sc .. "%]", pos)
if not pos then return s:sub(posa), #s + 1 end -- not terminated string
local part = s:sub(posa, pos)
return part, pos + 1
else
return nil, pos
end
end
end
-- based on LuaBalanced
local function match_comment(s, pos)
pos = pos or 1
if s:sub(pos, pos+1) ~= '--' then
return nil, pos
end
pos = pos + 2
if s:sub(pos,pos) == '[' then
local partt, post = match_string(s, pos)
if partt then
return '--' .. partt, post
end
end
local part; part, pos = s:match('^([^\n]*\n?)()', pos)
return '--' .. part, pos
end
-- note: matches invalid numbers too (for example, 0x)
local function match_numberlike(s, pos)
local hex = s:match('^0[xX]', pos)
if hex then pos = pos + #hex end
local longint = (hex and '^%x+' or '^%d+') .. '[uU]?[lL][lL]'
local mantissa1 = hex and '^%x+%.?%x*' or '^%d+%.?%d*'
local mantissa2 = hex and '^%.%x+' or '^%.%d+'
local exponent = hex and '^[pP][+%-]?%x*' or '^[eE][+%-]?%d*'
local imaginary = '^[iI]'
local tok = s:match(longint, pos)
if not tok then
tok = s:match(mantissa1, pos) or s:match(mantissa2, pos)
if tok then
local tok2 = s:match(exponent, pos + #tok)
if tok2 then tok = tok..tok2 end
tok2 = s:match(imaginary, pos + #tok)
if tok2 then tok = tok..tok2 end
end
end
return tok and (hex or '') .. tok or hex
end
local function newset(s)
local t = {}
for c in s:gmatch'.' do t[c] = true end
return t
end
local function qws(s)
local t = {}
for k in s:gmatch'%S+' do t[k] = true end
return t
end
local sym = newset("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_")
local dig = newset('0123456789')
local name = "([_A-Za-z][_A-Za-z0-9]*)"
local op = newset('=~<>.+-*/%^#=<>;:,.{}[]()')
op['=='] = true
op['<='] = true
op['>='] = true
op['~='] = true
op['..'] = true
op['<<'] = true
op['>>'] = true
op['//'] = true
local is_keyword = qws[[
and break do else elseif end false for function if
in local nil not or repeat return
then true until while goto]]
function M.lex(code, f, pos)
local pos = pos or 1
local tok = code:match('^#![^\n]*\n', pos) -- shebang
if tok then f('Shebang', tok, 1) pos = pos + #tok end
while pos <= #code do
local p2, n2, n1, n3 = code:match('^%s*()((%S)(%S?))', pos)
if not p2 then assert(code:sub(pos):match('^%s*$')); break end
pos = p2
if sym[n1] then
local tok = code:match('^'..name, pos)
assert(tok)
if is_keyword[tok] then
f('Keyword', tok, pos)
else
f('Id', tok, pos)
end
pos = pos + #tok
elseif n2 == '--' then
local tok, pos2 = match_comment(code, pos)
assert(tok)
f('Comment', tok, pos)
pos = pos2
elseif n2 == '::' then
local tok = code:match('^(::%s*'..name..'%s*::)', pos)
if tok then
f('Label', tok, pos)
pos = pos + #tok
else
f('Unknown', code:sub(pos, pos+1), pos) -- unterminated label
pos = pos + 2
end
elseif n1 == '\'' or n1 == '\"' or n2 == '[[' or n2 == '[=' then
local tok = match_string(code, pos)
if tok then
f('String', tok, pos)
pos = pos + #tok
else
f('Unknown', code:sub(pos), pos) -- unterminated string
pos = #code + 1
end
elseif dig[n1] or (n1 == '.' and dig[n3]) then
local tok = match_numberlike(code, pos)
assert(tok)
f('Number', tok, pos)
pos = pos + #tok
elseif op[n2] then
if n2 == '..' and code:match('^%.', pos+2) then
tok = '...'
else
tok = n2
end
f('Keyword', tok, pos)
pos = pos + #tok
elseif op[n1] then
local tok = n1
f('Keyword', tok, pos)
pos = pos + #tok
else
f('Unknown', n1, pos)
pos = pos + 1
end
end
end
local Stream = {}
Stream.__index = Stream
function Stream:next(val)
if self._next then
local _next = self._next
self._next = nil
return _next
else
self._next = nil
return self.f()
end
end
function Stream:peek()
if self._next then
return self._next
else
local _next = self.f()
self._next = _next
return _next
end
end
function M.lexc(code, f, pos)
local yield = coroutine.yield
local func = coroutine.wrap(f or function()
M.lex(code, function(tag, name, pos)
-- skip Comment tags as they may arbitrarily split statements and affects their processing
if tag ~= 'Comment' then yield {tag=tag, name, lineinfo=pos} end
end, pos)
yield {tag='Eof', lineinfo = #code+1}
end)
return setmetatable({f=func}, Stream)
end
return M