--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/js2lua.lua Fri Oct 15 15:17:17 2010 +0100
@@ -0,0 +1,113 @@
+local t = { op = {}, keyword = {}, name = {}, eos = {}, string = {}, regex = {} };
+
+local debug = function (...) io.stderr:write(table.concat({...}, "\t")); io.stderr:write"\n";end;
+local debug = function () end
+
+local function read_balanced(tokens, start, left, right)
+ local c = 0;
+ for i=start,#tokens do
+ if tokens[i].type == "op" then
+ local token = tokens[i].value;
+ if token == left then
+ c = c + 1;
+ elseif token == right then
+ c = c - 1;
+ end
+ end
+ if c == 0 then return i; end
+ end
+ return start;
+end
+
+local pair_op = { ["("] = ")", ["{"] = "}", ["["] = "]" };
+local function read_balanced_to(tokens, start, to)
+ local c = 0;
+ local i = start;
+ while i <= #tokens do
+ if tokens[i].type == "op" or tokens[i].type == "eos" then
+ local token = tokens[i].value;
+ if token == to then return i; end
+
+ if pair_op[token] then
+ i = read_balanced(tokens, i, token, pair_op[token]);
+ end
+ end
+ i = i + 1;
+ end
+ return nil;
+end
+
+function js2lua(tokens, write)
+
+-- Scan
+ local i = 1;
+ while i <= #tokens do
+ local token = tokens[i];
+ debug(token.type, token.value);
+ if token.type == "keyword" and token.value == "function" then
+ local j = read_balanced_to(tokens, i+3, ")"); -- Find matching )
+ j = j + 1; -- j now points to {
+ local k = read_balanced_to(tokens, j+1, "}");
+ table.remove(tokens, j); -- Remove {
+ tokens[k-1].type, tokens[k-1].value = "keyword", "end";
+ elseif token.type == "keyword" and token.value == "if" then
+ table.remove(tokens, i+1); -- Remove (
+ local j = read_balanced_to(tokens, i, ")");
+ tokens[j].type, tokens[j].value = "keyword", "then";
+
+ -- Make sure to end a single-statement block
+ if tokens[j+1].type ~= "op" or tokens[j+1].value ~= "{" then
+ local eos = read_balanced_to(tokens, j+1, ";");
+ if tokens[eos+1].type ~= "keyword" or tokens[eos+1].value ~= "else" then
+ table.insert(tokens, eos+1, { type = "keyword", value = "end" });
+ end
+ end
+ elseif token.type == "keyword" and token.value == "else" then
+ if tokens[i+1].type == "keyword" and tokens[i+1].value == "if" then
+ token.value = "elseif";
+ table.remove(tokens, i+1);
+
+ table.remove(tokens, i+1); -- Remove (
+ local j = read_balanced_to(tokens, i, ")");
+ tokens[j].type, tokens[j].value = "keyword", "then";
+ end
+
+ -- Make sure to end a single-statement block
+ if tokens[i+1].type ~= "op" or tokens[i+1].value ~= "{" then
+ local eos = read_balanced_to(tokens, i+1, ";");
+ if tokens[eos+1].type ~= "keyword" or tokens[eos+1].value ~= "else" then
+ table.insert(tokens, eos+1, { type = "keyword", value = "end" });
+ end
+ end
+ elseif token.type == "op" and token.value == "+" and tokens[i-1].type == "string" then
+ token.value = "..";
+ elseif token.type == "op" and token.value == "{" then
+ elseif token.type == "keyword" and token.value == "var" then
+ token.value = "local";
+ end
+ i = i + 1;
+ end
+
+-- Serialize
+ local last_token_type;
+ for _, token in ipairs(tokens) do
+ if token.type == "string" then
+ write("\"");
+ elseif token.type == "name" then
+ if last_token_type == "keyword" or last_token_type == "name" or last_token_type == "number" then
+ write(" ");
+ end
+ elseif token.type == "keyword" then
+ if last_token_type == "keyword" or last_token_type == "name" or last_token_type == "number" then
+ write(" ");
+ end
+ end
+ write(token.value);
+ if token.type == "string" then
+ write("\"");
+ end
+ last_token_type = token.type;
+ end
+end
+
+return js2lua;