Simple handling of try/catch directives.

lib/Template.js

@@ -64,8 +64,8 @@ Template.Constants = {
 };
 
 Template.Exception = function(code, message) {
-  this.code = code;
-  this.message = message;
+  this.type = code;
+  this.info = message;
 }
 Template.Exception.prototype.__proto__ = Error.prototype;
 Template.Exception.prototype.name = "Template.Exception";
@@ -276,10 +276,6 @@ Template.Context.prototype = {
     return ret;
   },
 
-  write: function(str) { this.out_arr.push(str); },
-
-  get_output: function() { return this.out_arr.join("") },
-
   nullObj: { toString: function() { return ''; } },
 
   dot_op: function Template$Context$dot_op(stash, segments, args) {
@@ -453,6 +449,19 @@ Template.Context.prototype = {
   // Default implementation is no file IO.
   load_file: function load_file(file) {
     throw new Template.Exception("NOT_FOUND", "File " + uneval(file) + " not found");
+  },
+
+  $catch: function $catch(err) {
+    var errType = typeof err == "object" &&
+                  err.constructor &&
+                  err.constructor.name
+                ? err.constructor.name
+                : 'undef';
+    if (!(err instanceof Template.Exception) ) {
+      err = new Template.Exception('undef', err);
+    }
+    this.dot_op(this.stash, ["error"], { assign: err } );
+    return err;
   }
 };
 
@@ -2027,6 +2036,7 @@ Template.Parser.prototype = {
       switch (this.token.type) {
         case ';':
           this.consumeToken();
+          c.signature = false;
           break;
         case 'DEFAULT':
           c.signature = this.consumeToken();
@@ -2092,12 +2102,12 @@ Template.Interpreter.prototype = {
   var out_arr = []; ctx.StopIteration = StopIteration || 'StopIteration'; \
   function __perl_truth(val) { return (!!val && val != '0' && val !== ctx.nullObj) ? val : '' };\
   function __not_perl_truth(val) { return (!!val && val != '0' && val !== ctx.nullObj) ? '' : 1 };\
-  function write() { out_arr = out_arr.concat(Array.prototype.slice.apply(arguments)); };\n\
+  function write() { out_arr = out_arr.concat(Array.slice(arguments)); };\n\
   try {\n",
 
   postlude: "\n\
   }\n\
-  catch (e) { if (!(e instanceof Template.Exception && e.code == 'stop')) throw e; } \n\
+  catch (e) { if (!(e instanceof Template.Exception && e.type == 'stop')) throw e; } \n\
   return out_arr.join('');\n\
 }",
 
@@ -2113,9 +2123,9 @@ Template.Interpreter.prototype = {
       // check for things like GET, SET or CALL
       // Not everything writes directly.
       var write = ['IF', 'FOR', 'CALL', 'setlist', 'DEFAULT', 'UNLESS', 'BLOCK', 
-                   'NEXT', 'LAST', 'WHILE', 'SWITCH'
+                   'NEXT', 'LAST', 'WHILE', 'SWITCH', 'TRY', 'THROW', 'CATCH'
                   ].indexOf(chunk.type) == -1;
-      var add_semicolon = write;// || chunk.type == 'BLOCK';
+      var add_semicolon = write || ['THROW'].indexOf(chunk.type) != -1;
 
       if (chunk.toSource)
         output += '/* ' + chunk.toSource() + ' */\n';
@@ -2418,6 +2428,40 @@ Template.Interpreter.prototype = {
         ret += '}\n';
         return ret;
 
+      case 'TRY':
+        var ret = "try {\n";
+
+        var body = this.walk(term.tryBlock);
+        ret += body.replace(/^/gm, '  ');
+
+        ret += "}\n";
+
+        if (term.catches.length) {
+          ret += 'catch ($e) { $e = ctx.$catch($e); \n';
+
+          for (var i in term.catches) {
+            var c = term.catches[i];
+            if (c.signature == 'DEFAULT') {}
+            else if (c.signature) {}
+            else {
+              var body = this.walk(c.block);
+              ret += body.replace(/^/gm, '  ');
+            }
+          }
+
+          ret += '}\n';
+        }
+        if (term['final'].length) {
+        }
+
+        // TT doesn't require a CATCH or FINAL block. JS does
+        if (!term.catches.length && !term['final'].length) {
+          ret += "catch ($e) {}\n"
+        }
+
+        return ret;
+      case 'THROW':
+        return "throw " + this.handle_nameargs(term);
       default:
         throw new Error('Unhandled ' + term.toSource());
     }