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local targetName = "Lua 5.3"
return function(code, ast, options)
--- Line mapping
local lastInputPos = 1 -- last token position in the input code
local prevLinePos = 1 -- last token position in the previous line of code in the input code
local lastSource = options.chunkname or "nil" -- last found code source name (from the original file)
local lastLine = 1 -- last found line number (from the original file)
--- Newline management
local indentLevel = 0
-- Returns a newline.
local function newline()
local r = options.newline..string.rep(options.indentation, indentLevel)
if options.mapLines then
local sub = code:sub(lastInputPos)
local source, line = sub:sub(1, sub:find("\n")):match(".*%-%- (.-)%:(%d+)\n")
if source and line then
lastSource = source
lastLine = tonumber(line)
else
for _ in code:sub(prevLinePos, lastInputPos):gmatch("\n") do
lastLine += 1
end
end
prevLinePos = lastInputPos
r = " -- "..lastSource..":"..lastLine..r
end
return r
end
-- Returns a newline and add one level of indentation.
local function indent()
indentLevel += 1
return newline()
end
-- Returns a newline and remove one level of indentation.
local function unindent()
indentLevel -= 1
return newline()
end
--- State stacks
-- Used for context-sensitive syntax.
local states = {
push = {}, -- push stack variable names
destructuring = {}, -- list of variable that need to be assigned from a destructure {id = "parent variable", "field1", "field2"...}
scope = {} -- list of variables defined in the current scope
}
-- Push a new value on top of the stack "name". Returns an empty string for chaining.
local function push(name, state)
table.insert(states[name], state)
return ""
end
-- Remove the value on top of the stack "name". Returns an empty string for chaining.
local function pop(name)
table.remove(states[name])
return ""
end
-- Set the value on top of the stack "name". Returns an empty string for chaining.
local function set(name, state)
states[name][#states[name]] = state
return ""
end
-- Returns the value on top of the stack "name".
local function peek(name)
return states[name][#states[name]]
end
--- Variable management
-- Returns the prefixed variable name.
local function var(name)
return options.variablePrefix..name
end
-- Returns the prefixed temporary variable name.
local function tmp()
local scope = peek("scope")
local var = "%s_%s":format(options.variablePrefix, #scope)
table.insert(scope, var)
return var
end
--- Module management
local required = {} -- { ["full require expression"] = true, ... }
local requireStr = ""
-- Add the module "mod" to the list of modules to require, and load its field "field" (or the whole module if nil) into the variable "name".
local function addRequire(mod, name, field)
local req = "require(%q)%s":format(mod, field and "."..field or "")
if not required[req] then
requireStr ..= "local %s = %s%s":format(var(name), req, options.newline)
required[req] = true
end
end
--- AST traversal helpers
local loop = { "While", "Repeat", "Fornum", "Forin", "WhileExpr", "RepeatExpr", "FornumExpr", "ForinExpr" } -- loops tags (can contain continue)
local func = { "Function", "TableCompr", "DoExpr", "WhileExpr", "RepeatExpr", "IfExpr", "FornumExpr", "ForinExpr" } -- function scope tags (can contain push)
-- Returns the first node or subnode from the list "list" which tag is in the list "tags", or nil if there were none.
-- Won't recursively follow nodes which have a tag in "nofollow".
local function any(list, tags, nofollow={})
local tagsCheck = {}
for _, tag in ipairs(tags) do
tagsCheck[tag] = true
end
local nofollowCheck = {}
for _, tag in ipairs(nofollow) do
nofollowCheck[tag] = true
end
for _, node in ipairs(list) do
if type(node) == "table" then
if tagsCheck[node.tag] then
return node
end
if not nofollowCheck[node.tag] then
local r = any(node, tags, nofollow)
if r then return r end
end
end
end
return nil
end
-- Like any, but returns a list of every node found.
-- Order: in the order of the list, from the deepest to the nearest
local function search(list, tags, nofollow={})
local tagsCheck = {}
for _, tag in ipairs(tags) do
tagsCheck[tag] = true
end
local nofollowCheck = {}
for _, tag in ipairs(nofollow) do
nofollowCheck[tag] = true
end
local found = {}
for _, node in ipairs(list) do
if type(node) == "table" then
if not nofollowCheck[node.tag] then
for _, n in ipairs(search(node, tags, nofollow)) do
table.insert(found, n)
end
end
if tagsCheck[node.tag] then
table.insert(found, node)
end
end
end
return found
end
-- Returns true if the all the nodes in list have their type in tags.
local function all(list, tags)
for _, node in ipairs(list) do
local ok = false
for _, tag in ipairs(tags) do
if node.tag == tag then
ok = true
break
end
end
if not ok then
return false
end
end
return true
end
--- Lua compiler
local tags
-- Recursively returns the compiled AST Lua code, set "forceTag" to override the tag type and pass additional arguments to the tag constructor if needed.
local function lua(ast, forceTag, ...)
if options.mapLines and ast.pos then
lastInputPos = ast.pos
end
return tags[forceTag or ast.tag](ast, ...)
end
--- Lua function calls writer
local UNPACK = (list, i, j) -- table.unpack
return "table.unpack("..list..(i and (", "..i..(j and (", "..j) or "")) or "")..")"
end
local APPEND = (t, toAppend) -- append values "toAppend" (multiple values possible) to t
return "do"..indent().."local "..var("a").." = table.pack("..toAppend..")"..newline().."table.move("..var("a")..", 1, "..var("a")..".n, #"..t.."+1, "..t..")"..unindent().."end"
end
local CONTINUE_START = () -- at the start of loops using continue
return "do"..indent()
end
local CONTINUE_STOP = () -- at the start of loops using continue
return unindent().."end"..newline().."::"..var"continue".."::"
end
local DESTRUCTURING_ASSIGN = (destructured, newlineAfter=false, noLocal=false) -- to define values from a destructuring assignement
local vars = {}
local values = {}
for _, list in ipairs(destructured) do
for _, v in ipairs(list) do
local var, val
if v.tag == "Id" then
var = v
val = { tag = "Index", { tag = "Id", list.id }, { tag = "String", v[1] } }
elseif v.tag == "Pair" then
var = v[2]
val = { tag = "Index", { tag = "Id", list.id }, v[1] }
else
error("unknown destructuring element type: "..tostring(v.tag))
end
if destructured.rightOp and destructured.leftOp then
val = { tag = "Op", destructured.rightOp, var, { tag = "Op", destructured.leftOp, val, var } }
elseif destructured.rightOp then
val = { tag = "Op", destructured.rightOp, var, val }
elseif destructured.leftOp then
val = { tag = "Op", destructured.leftOp, val, var }
end
table.insert(vars, lua(var))
table.insert(values, lua(val))
end
end
if #vars > 0 then
local decl = noLocal and "" or "local "
if newlineAfter then
return decl..table.concat(vars, ", ").." = "..table.concat(values, ", ")..newline()
else
return newline()..decl..table.concat(vars, ", ").." = "..table.concat(values, ", ")
end
else
return ""
end
end
--- Tag constructors
tags = setmetatable({
-- block: { stat* } --
Block = (t)
local hasPush = peek("push") == nil and any(t, { "Push" }, func) -- push in block and push context not yet defined
if hasPush and hasPush == t[#t] then -- if the first push is the last statement, it's just a return
hasPush.tag = "Return"
hasPush = false
end
local r = push("scope", {})
if hasPush then
r ..= push("push", var"push").."local "..var"push".." = {}"..newline()
end
for i=1, #t-1, 1 do
r ..= lua(t[i])..newline()
end
if t[#t] then
r ..= lua(t[#t])
end
if hasPush and (t[#t] and t[#t].tag ~= "Return") then -- add return only if needed
r ..= newline().."return "..UNPACK(var"push")..pop("push")
end
return r..pop("scope")
end,
-- stat --
-- Do{ stat* }
Do = (t)
return "do"..indent()..lua(t, "Block")..unindent().."end"
end,
-- Set{ {lhs+} (opid? = opid?)? {expr+} }
Set = (t)
-- extract vars and values
local expr = t[#t]
local vars, values = {}, {}
local destructuringVars, destructuringValues = {}, {}
for i, n in ipairs(t[1]) do
if n.tag == "DestructuringId" then
table.insert(destructuringVars, n)
table.insert(destructuringValues, expr[i])
else
table.insert(vars, n)
table.insert(values, expr[i])
end
end
--
if #t == 2 or #t == 3 then
local r = ""
if #vars > 0 then
r = lua(vars, "_lhs").." = "..lua(values, "_lhs")
end
if #destructuringVars > 0 then
local destructured = {}
r ..= "local "..push("destructuring", destructured)..lua(destructuringVars, "_lhs")..pop("destructuring").." = "..lua(destructuringValues, "_lhs")
return r..DESTRUCTURING_ASSIGN(destructured, nil, true)
end
return r
elseif #t == 4 then
if t[3] == "=" then
local r = ""
if #vars > 0 then
r ..= lua(vars, "_lhs").." = "..lua({ t[2], vars[1], { tag = "Paren", values[1] } }, "Op")
for i=2, math.min(#t[4], #vars), 1 do
r ..= ", "..lua({ t[2], vars[i], { tag = "Paren", values[i] } }, "Op")
end
end
if #destructuringVars > 0 then
local destructured = { rightOp = t[2] }
r ..= "local "..push("destructuring", destructured)..lua(destructuringVars, "_lhs")..pop("destructuring").." = "..lua(destructuringValues, "_lhs")
return r..DESTRUCTURING_ASSIGN(destructured, nil, true)
end
return r
else
local r = ""
if #vars > 0 then
r ..= lua(vars, "_lhs").." = "..lua({ t[3], { tag = "Paren", values[1] }, vars[1] }, "Op")
for i=2, math.min(#t[4], #t[1]), 1 do
r ..= ", "..lua({ t[3], { tag = "Paren", values[i] }, vars[i] }, "Op")
end
end
if #destructuringVars > 0 then
local destructured = { leftOp = t[3] }
r ..= "local "..push("destructuring", destructured)..lua(destructuringVars, "_lhs")..pop("destructuring").." = "..lua(destructuringValues, "_lhs")
return r..DESTRUCTURING_ASSIGN(destructured, nil, true)
end
return r
end
else -- You are mad.
local r = ""
if #vars > 0 then
r ..= lua(vars, "_lhs").." = "..lua({ t[2], vars[1], { tag = "Op", t[4], { tag = "Paren", values[1] }, vars[1] } }, "Op")
for i=2, math.min(#t[5], #t[1]), 1 do
r ..= ", "..lua({ t[2], vars[i], { tag = "Op", t[4], { tag = "Paren", values[i] }, vars[i] } }, "Op")
end
end
if #destructuringVars > 0 then
local destructured = { rightOp = t[2], leftOp = t[4] }
r ..= "local "..push("destructuring", destructured)..lua(destructuringVars, "_lhs")..pop("destructuring").." = "..lua(destructuringValues, "_lhs")
return r..DESTRUCTURING_ASSIGN(destructured, nil, true)
end
return r
end
end,
-- While{ expr block }
While = (t)
local r = ""
local hasContinue = any(t[2], { "Continue" }, loop)
local lets = search({ t[1] }, { "LetExpr" })
if #lets > 0 then
r ..= "do"..indent()
for _, l in ipairs(lets) do
r ..= lua(l, "Let")..newline()
end
end
r ..= "while "..lua(t[1]).." do"..indent()
if #lets > 0 then
r ..= "do"..indent()
end
if hasContinue then
r ..= CONTINUE_START()
end
r ..= lua(t[2])
if hasContinue then
r ..= CONTINUE_STOP()
end
r ..= unindent().."end"
if #lets > 0 then
for _, l in ipairs(lets) do
r ..= newline()..lua(l, "Set")
end
r ..= unindent().."end"..unindent().."end"
end
return r
end,
-- Repeat{ block expr }
Repeat = (t)
local hasContinue = any(t[1], { "Continue" }, loop)
local r = "repeat"..indent()
if hasContinue then
r ..= CONTINUE_START()
end
r ..= lua(t[1])
if hasContinue then
r ..= CONTINUE_STOP()
end
r ..= unindent().."until "..lua(t[2])
return r
end,
-- If{ (lexpr block)+ block? }
If = (t)
local r = ""
local toClose = 0 -- blocks that need to be closed at the end of the if
local lets = search({ t[1] }, { "LetExpr" })
if #lets > 0 then
r ..= "do"..indent()
toClose += 1
for _, l in ipairs(lets) do
r ..= lua(l, "Let")..newline()
end
end
r ..= "if "..lua(t[1]).." then"..indent()..lua(t[2])..unindent()
for i=3, #t-1, 2 do
lets = search({ t[i] }, { "LetExpr" })
if #lets > 0 then
r ..= "else"..indent()
toClose += 1
for _, l in ipairs(lets) do
r ..= lua(l, "Let")..newline()
end
else
r ..= "else"
end
r ..= "if "..lua(t[i]).." then"..indent()..lua(t[i+1])..unindent()
end
if #t % 2 == 1 then
r ..= "else"..indent()..lua(t[#t])..unindent()
end
r ..= "end"
for i=1, toClose do
r ..= unindent().."end"
end
return r
end,
-- Fornum{ ident expr expr expr? block }
Fornum = (t)
local r = "for "..lua(t[1]).." = "..lua(t[2])..", "..lua(t[3])
if #t == 5 then
local hasContinue = any(t[5], { "Continue" }, loop)
r ..= ", "..lua(t[4]).." do"..indent()
if hasContinue then
r ..= CONTINUE_START()
end
r ..= lua(t[5])
if hasContinue then
r ..= CONTINUE_STOP()
end
return r..unindent().."end"
else
local hasContinue = any(t[4], { "Continue" }, loop)
r ..= " do"..indent()
if hasContinue then
r ..= CONTINUE_START()
end
r ..= lua(t[4])
if hasContinue then
r ..= CONTINUE_STOP()
end
return r..unindent().."end"
end
end,
-- Forin{ {ident+} {expr+} block }
Forin = (t)
local destructured = {}
local hasContinue = any(t[3], { "Continue" }, loop)
local r = "for "..push("destructuring", destructured)..lua(t[1], "_lhs")..pop("destructuring").." in "..lua(t[2], "_lhs").." do"..indent()
if hasContinue then
r ..= CONTINUE_START()
end
r ..= DESTRUCTURING_ASSIGN(destructured, true)..lua(t[3])
if hasContinue then
r ..= CONTINUE_STOP()
end
return r..unindent().."end"
end,
-- Local{ {ident+} {expr+}? }
Local = (t)
local destructured = {}
local r = "local "..push("destructuring", destructured)..lua(t[1], "_lhs")..pop("destructuring")
if t[2][1] then
r ..= " = "..lua(t[2], "_lhs")
end
return r..DESTRUCTURING_ASSIGN(destructured)
end,
-- Let{ {ident+} {expr+}? }
Let = (t)
local destructured = {}
local nameList = push("destructuring", destructured)..lua(t[1], "_lhs")..pop("destructuring")
local r = "local "..nameList
if t[2][1] then
if all(t[2], { "Nil", "Dots", "Boolean", "Number", "String" }) then -- predeclaration doesn't matter here
r ..= " = "..lua(t[2], "_lhs")
else
r ..= newline()..nameList.." = "..lua(t[2], "_lhs")
end
end
return r..DESTRUCTURING_ASSIGN(destructured)
end,
-- Localrec{ {ident} {expr} }
Localrec = (t)
return "local function "..lua(t[1][1])..lua(t[2][1], "_functionWithoutKeyword")
end,
-- Goto{ <string> }
Goto = (t)
return "goto "..lua(t, "Id")
end,
-- Label{ <string> }
Label = (t)
return "::"..lua(t, "Id").."::"
end,
-- Return{ <expr*> }
Return = (t)
local push = peek("push")
if push then
local r = ""
for _, val in ipairs(t) do
r ..= push.."[#"..push.."+1] = "..lua(val)..newline()
end
return r.."return "..UNPACK(push)
else
return "return "..lua(t, "_lhs")
end
end,
-- Push{ <expr*> }
Push = (t)
local var = assert(peek("push"), "no context given for push")
r = ""
for i=1, #t-1, 1 do
r ..= var.."[#"..var.."+1] = "..lua(t[i])..newline()
end
if t[#t] then
if t[#t].tag == "Call" then
r ..= APPEND(var, lua(t[#t]))
else
r ..= var.."[#"..var.."+1] = "..lua(t[#t])
end
end
return r
end,
-- Break
Break = ()
return "break"
end,
-- Continue
Continue = ()
return "goto "..var"continue"
end,
-- apply (below)
-- expr --
-- Nil
Nil = ()
return "nil"
end,
-- Dots
Dots = ()
return "..."
end,
-- Boolean{ <boolean> }
Boolean = (t)
return tostring(t[1])
end,
-- Number{ <string> }
Number = (t)
return tostring(t[1])
end,
-- String{ <string> }
String = (t)
return "%q":format(t[1])
end,
-- Function{ { ( `ParPair{ Id expr } | `Id{ <string> } )* `Dots? } block }
_functionWithoutKeyword = (t)
local r = "("
local decl = {}
if t[1][1] then
if t[1][1].tag == "ParPair" then
local id = lua(t[1][1][1])
indentLevel += 1
table.insert(decl, "if "..id.." == nil then "..id.." = "..lua(t[1][1][2]).." end")
indentLevel -= 1
r ..= id
else
r ..= lua(t[1][1])
end
for i=2, #t[1], 1 do
if t[1][i].tag == "ParPair" then
local id = lua(t[1][i][1])
indentLevel += 1
table.insert(decl, "if "..id.." == nil then "..id.." = "..lua(t[1][i][2]).." end")
indentLevel -= 1
r ..= ", " ..id
else
r ..= ", "..lua(t[1][i])
end
end
end
r ..= ")"..indent()
for _, d in ipairs(decl) do
r ..= d..newline()
end
if t[2][#t[2]] and t[2][#t[2]].tag == "Push" then -- convert final push to return
t[2][#t[2]].tag = "Return"
end
local hasPush = any(t[2], { "Push" }, func)
if hasPush then
r ..= push("push", var"push").."local "..var"push".." = {}"..newline()
else
push("push", false) -- no push here (make sure higher push doesn't affect us)
end
r ..= lua(t[2])
if hasPush and (t[2][#t[2]] and t[2][#t[2]].tag ~= "Return") then -- add return only if needed
r ..= newline().."return "..UNPACK(var"push")
end
pop("push")
return r..unindent().."end"
end,
Function = (t)
return "function"..lua(t, "_functionWithoutKeyword")
end,
-- Table{ ( `Pair{ expr expr } | expr )* }
Pair = (t)
return "["..lua(t[1]).."] = "..lua(t[2])
end,
Table = (t)
if #t == 0 then
return "{}"
elseif #t == 1 then
return "{ "..lua(t, "_lhs").." }"
else
return "{"..indent()..lua(t, "_lhs", nil, true)..unindent().."}"
end
end,
-- TableCompr{ block }
TableCompr = (t)
return push("push", "self").."(function()"..indent().."local self = {}"..newline()..lua(t[1])..newline().."return self"..unindent().."end)()"..pop("push")
end,
-- Op{ opid expr expr? }
Op = (t)
local r
if #t == 2 then
if type(tags._opid[t[1]]) == "string" then
r = tags._opid[t[1]].." "..lua(t[2])
else
r = tags._opid[t[1]](t[2])
end
else
if type(tags._opid[t[1]]) == "string" then
r = lua(t[2]).." "..tags._opid[t[1]].." "..lua(t[3])
else
r = tags._opid[t[1]](t[2], t[3])
end
end
return r
end,
-- Paren{ expr }
Paren = (t)
return "("..lua(t[1])..")"
end,
-- MethodStub{ expr expr }
MethodStub = (t)
return "(function()"..indent() ..
"local "..var"object".." = "..lua(t[1])..newline()..
"local "..var"method".." = "..var"object".."."..lua(t[2], "Id")..newline() ..
"if "..var"method".." == nil then return nil end"..newline()..
"return function(...) return "..var"method".."("..var"object"..", ...) end"..unindent()..
"end)()"
end,
-- SafeMethodStub{ expr expr }
SafeMethodStub = (t)
return "(function()"..indent() ..
"local "..var"object".." = "..lua(t[1])..newline()..
"if "..var"object".." == nil then return nil end"..newline()..
"local "..var"method".." = "..var"object".."."..lua(t[2], "Id")..newline() ..
"if "..var"method".." == nil then return nil end"..newline()..
"return function(...) return "..var"method".."("..var"object"..", ...) end"..unindent()..
"end)()"
end,
-- statexpr (below)
-- apply (below)
-- lhs (below)
-- lexpr --
LetExpr = (t)
return lua(t[1][1])
end,
-- statexpr --
_statexpr = (t, stat)
local hasPush = any(t, { "Push" }, func)
local r = "(function()"..indent()
if hasPush then
r ..= push("push", var"push").."local "..var"push".." = {}"..newline()
else
push("push", false) -- no push here (make sure higher push don't affect us)
end
r ..= lua(t, stat)
if hasPush then
r ..= newline().."return "..UNPACK(var"push")
end
pop("push")
r ..= unindent().."end)()"
return r
end,
-- DoExpr{ stat* }
DoExpr = (t)
if t[#t].tag == "Push" then -- convert final push to return
t[#t].tag = "Return"
end
return lua(t, "_statexpr", "Do")
end,
-- WhileExpr{ expr block }
WhileExpr = (t)
return lua(t, "_statexpr", "While")
end,
-- RepeatExpr{ block expr }
RepeatExpr = (t)
return lua(t, "_statexpr", "Repeat")
end,
-- IfExpr{ (expr block)+ block? }
IfExpr = (t)
for i=2, #t do -- convert final pushes to returns
local block = t[i]
if block[#block] and block[#block].tag == "Push" then
block[#block].tag = "Return"
end
end
return lua(t, "_statexpr", "If")
end,
-- FornumExpr{ ident expr expr expr? block }
FornumExpr = (t)
return lua(t, "_statexpr", "Fornum")
end,
-- ForinExpr{ {ident+} {expr+} block }
ForinExpr = (t)
return lua(t, "_statexpr", "Forin")
end,
-- apply --
-- Call{ expr expr* }
Call = (t)
if t[1].tag == "String" or t[1].tag == "Table" then
return "("..lua(t[1])..")("..lua(t, "_lhs", 2)..")"
elseif t[1].tag == "MethodStub" then -- method call
if t[1][1].tag == "String" or t[1][1].tag == "Table" then
return "("..lua(t[1][1]).."):"..lua(t[1][2], "Id").."("..lua(t, "_lhs", 2)..")"
else
return lua(t[1][1])..":"..lua(t[1][2], "Id").."("..lua(t, "_lhs", 2)..")"
end
else
return lua(t[1]).."("..lua(t, "_lhs", 2)..")"
end
end,
-- SafeCall{ expr expr* }
SafeCall = (t)
if t[1].tag ~= "Id" then -- side effect possible, only evaluate each expr once (or already in a safe context)
return lua(t, "SafeIndex")
else -- no side effects possible
return "("..lua(t[1]).." ~= nil and "..lua(t[1]).."("..lua(t, "_lhs", 2)..") or nil)"
end
end,
-- lhs --
_lhs = (t, start=1, newlines)
local r
if t[start] then
r = lua(t[start])
for i=start+1, #t, 1 do
r ..= ","..(newlines and newline() or " ")..lua(t[i])
end
else
r = ""
end
return r
end,
-- Id{ <string> }
Id = (t)
return t[1]
end,
-- DestructuringId{ Id | Pair+ }
DestructuringId = (t)
if t.id then -- destructing already done before, use parent variable as id
return t.id
else
local d = assert(peek("destructuring"), "DestructuringId not in a destructurable assignement")
local vars = { id = tmp() }
for j=1, #t, 1 do
table.insert(vars, t[j])
end
table.insert(d, vars)
t.id = vars.id
return vars.id
end
end,
-- Index{ expr expr }
Index = (t)
if t[1].tag == "String" or t[1].tag == "Table" then
return "("..lua(t[1])..")["..lua(t[2]).."]"
else
return lua(t[1]).."["..lua(t[2]).."]"
end
end,
-- SafeIndex{ expr expr }
SafeIndex = (t)
if t[1].tag ~= "Id" then -- side effect possible, only evaluate each expr once (or already in a safe context)
local l = {} -- list of immediately chained safeindex, from deepest to nearest (to simply generated code)
while t.tag == "SafeIndex" or t.tag == "SafeCall" do
table.insert(l, 1, t)
t = t[1]
end
local r = "(function()"..indent().."local "..var"safe".." = "..lua(l[1][1])..newline() -- base expr
for _, e in ipairs(l) do
r ..= "if "..var"safe".." == nil then return nil end"..newline()
if e.tag == "SafeIndex" then
r ..= var"safe".." = "..var"safe".."["..lua(e[2]).."]"..newline()
else
r ..= var"safe".." = "..var"safe".."("..lua(e, "_lhs", 2)..")"..newline()
end
end
r ..= "return "..var"safe"..unindent().."end)()"
return r
else -- no side effects possible
return "("..lua(t[1]).." ~= nil and "..lua(t[1]).."["..lua(t[2]).."] or nil)"
end
end,
-- opid --
_opid = {
add = "+", sub = "-", mul = "*", div = "/",
idiv = "//", mod = "%", pow = "^", concat = "..",
band = "&", bor = "|", bxor = "~", shl = "<<", shr = ">>",
eq = "==", ne = "~=", lt = "<", gt = ">", le = "<=", ge = ">=",
["and"] = "and", ["or"] = "or", unm = "-", len = "#", bnot = "~", ["not"] = "not"
}
}, {
__index = (self, key)
error("don't know how to compile a "..tostring(key).." to "..targetName)
end
})
#placeholder("patch")
local code = lua(ast)..newline()
return requireStr..code
end
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