Scala Parse String Class and Compile in Run-Time -


i want implement function in scala can parse string of source code (a class object) , compile object in run time.

for example, function have tried far. goal run compiled in run-time environment, can use constructor or function. code has run-time error don't understand how fix reflect class error. thanks!

object test {         def main(args: array[string]): unit = {             val m = universe.runtimemirror(getclass.getclassloader)             val tb = m.mktoolbox()             val clazz = tb.compile(tb.parse("class insideclass {\n    val model_field = 5\n   def insideclass(model: int) = {\n        val model_field = model \n    } \n\n    def test() : int = {\n        model_field\n    }\n\n}\nscala.reflect.classtag[insideclass].runtimeclass"))().asinstanceof[class[_]]             val classinside = universe.typeof[class[_]].typesymbol.asclass             val ctor = universe.typeof[class[_]].declaration(universe.nme.constructor).asmethod             val cm=m.reflectclass(classinside)             val ctorm=cm.reflectconstructor(ctor)             println(ctorm(10).test())         }     }

the problem outside compiler not know "insideclass" exists class definition. 1 solution make inside class extend other class know both inside , outside compiler, example function[int, int]. need rename "test" method "apply" in case.

val clazz = tb.compile(tb.parse("class persondata(x:int) extends  function[int, int] {\n val allen = x.toint\n\n override def apply(x:int):int = allen}\n scala.reflect.classtag[persondata].runtimeclass"))().asinstanceof[class[_]]  val ctor = clazz.getdeclaredconstructors()(0)  val instance = ctor.newinstance(new integer(1)) // cast can succeed because outside knows function[int, int] println(instance.asinstanceof[function[int, int]].apply(1))

Comments

Post a Comment

Popular posts from this blog

sql server - Cannot query correctly (MSSQL - PHP - JSON) -

i have little problem on project. , turns out query result returns nothing when value of first name or last name has 'ñ' in it. here's code config.php: <?php ini_set('mssql.charset', 'utf-8'); header('content-type: text/html; charset=utf-8'); $servername = "192.168.1.21"; /* ip add of db server */ $connection = array("database" => "db", "uid" => "?", "pwd" => "***"); $conn = sqlsrv_connect($servername, $connection); if(!$conn){ echo "connection not established."; die(print_r(sqlsrv_errors(), true)); } ?> myquery: $idnumber = $_post["idnum"]; $response = array(); $query2 = "select clname, cfname, cmname, cqualifier student cidno = '$idnumber'"; try{ $stmt2 = sqlsrv_query($conn, $query2); } catch(pdoexeption $ex){ $response["success"] = 0; $response["message"] = "d...
Read more

php - trouble displaying mysqli database results in correct order -

i have table in database stores events , date expire. want display events on website display current events first expired events after? i have tried following sql $sql = "select noticeid, notice, noticedesc, noticeimg, noticedate, expirydate tbl_notices group noticeid ,expired order expirydate asc"; but returns expired results first due expirydate being ordered asc in query. my tbl_notice structure looks this noticeid => int(4) notice => varchar(100) noticedesc => text noticedate => timestamp noticeimg => varchar(40) expirydate => datetime expired => int(1) 0 current or 1 expired my php code is $sql = "select noticeid, notice, noticedesc, noticeimg, noticedate, expirydate tbl_notices group noticeid ,expired order expirydate asc"; $result = mysqli_query($conn,$sql); if ($result->num_rows > 0) { // output data of each row while($row = $result->fetch_assoc()) { ...
Read more

C++ Linked List -

i trying create linked list download txt file , use linked list handle file line line. when handling downloaded linked list operations performed on such text editor would. encountering problems however. seems "node(string value)" section of code has wrong though original node() declaration no arguments passes. unable figure out quite is. node.h class node { public: node(); node(string value); void setnext(node *nextnode); // allows user set "next" pointer of node points friend class linkedlist; private: string data; // data box node* next; // pointer box }; node.cpp # include <string> # include "node.h" using namespace std; node::node() { data = ""; next = null; } node::node(string value) { data = value; next = null; } void node::setnext(node *nextnode) // allows user set "next" pointer of node points { this->next = nextnode; } your #include <string> ...
Read more