Issue 427 - Desugar arrow functions to normal or bound functions

scripts/astDecompile.js

 let global = this;
 function decompileAST(ast) {
   let func = global["decompile" + ast.type];
   if (!func)
     throw "Unknown type " + ast.type;
   return func(ast);
 }
 
 function decompileProgram(ast) {
   return [decompileAST(stmt) for each (stmt in ast.body)].join('\n');
@@ skipping 231 matching lines @@
     else
       throw "Unknown kind " + prop.kind;
   }
   return "{\n" + props.join(",\n") + "}";
 }
 
 function decompileFunctionExpression(ast) {
   return decompileFunctionDeclaration(ast);
 }
 
+function decompileArrowExpression(ast) {
+  let str = "(" + ast.params.map(decompileAST).join(", ") + ")";
+  str += " => " + decompileAST(ast.body);
+  return str;
+}
+
 function decompileSequenceExpression(ast) {
   return "(" + [decompileExpr(e, ast) for each (e in ast.expressions)].join(", ") + ")";
 }
 
 function decompileUnaryExpression(ast) {
   if (ast.prefix)
     return ast.operator + " " + decompileExpr(ast.argument, ast);
   throw "ER, wtf?";
 }
 
@@ skipping 226 matching lines @@
   return "<!--" + ast.comment + "-->";
 }
 
 function decompileXMLProcessingInstruction(ast) {
   return "<?" + ast.target + (ast.contents ? " " + ast.contents : "") + "?>";
 }
 
 function process_js(ast) {
     _print(decompileAST(ast));
 }