code: function(node) {
  		if (node.code) {
  			// remove trailing whitespace for single-line predicates
  			var code = node.code.replace(/[ \t]+$/, '');
  			// wrap with a function, to prevent spurious errors caused
  			// by redeclarations or multiple returns in a block.
  			rulesSource += tab + '(function() {\n' + code + '\n' +
  				tab + '})();\n';
  		}
  	}
docs: Collect all the code blocks in the AST.