booster::regex:unmatched parentheses, at offset 4

config.js

{
  "service" : {
    "api" : "http",
    "port" : 8080
  },
  "http" : {
    "script" : "/myapp"
  }
}

myapp.cpp

#include <cppcms/application.h>
#include <cppcms/applications_pool.h>
#include <cppcms/service.h>
#include <cppcms/http_response.h>
#include <cppcms/url_dispatcher.h>
#include <cppcms/url_mapper.h>

#include <exception>

using std::exception;
using std::cerr;

class number : public cppcms::application{
public:
    number(cppcms::service &srv);

    void even();
    void odd();
    void prime();
    void all();
};

number::number(cppcms::service &srv) : cppcms::application(srv){
    dispatcher().assign("/odd)", &number::odd, this);
    mapper().assign("odd", "/odd");

    dispatcher().assign("/even", &number::even, this);
    mapper().assign("even", "/even");

    dispatcher().assign("/prime", &number::prime, this);
    mapper().assign("prime", "/prime");

    dispatcher().assign("", &number::all, this);
    mapper().assign("");
}

void number::odd(){
    response().out()<<"Odd";
}

void number::even(){
    response().out()<<"Even";
}

void number::prime(){
    response().out()<<"Prime";
}

void number::all(){
    response().out()<<url(".")<<"<br>"<<url("/")<<"<br>"<<url("/letter");
}

class letter : public cppcms::application{
public:
    letter(cppcms::service &srv);

    void capital();
    void small();
    void all();
};

letter::letter(cppcms::service &srv) : cppcms::application(srv){
    dispatcher().assign("/capital)", &letter::capital, this);
    mapper().assign("capital", "/capital");

    dispatcher().assign("/small", &letter::small, this);
    mapper().assign("small", "/small");


    dispatcher().assign("", &letter::all, this);
    mapper().assign("");
}

void letter::small(){
    response().out()<<"Small";
}

void letter::capital(){
    response().out()<<"Cap";
}

void letter::all(){
    response().out()<<url(".")<<"<br>"<<url("/")<<"<br>"<<url("/number");
}

class myapp : public cppcms::application{
public:
    myapp(cppcms::service &srv);

    void describe();
};

myapp::myapp(cppcms::service &srv) : cppcms::application(srv){
    attach(new number(srv), "number", "/number{1}", "/number(/(.*))?", 1);
    attach(new letter(srv), "letter", "/letter{1}", "/letter(/(.*))?", 1);

    dispatcher().assign("", &myapp::describe, this);
    mapper().assign("");


    mapper().root("/myapp");
}

void myapp::describe(){
    response().out()<<url(".")<<"<br>"<<url("/")<<"<br>"<<url("/letter")<<
    "\n"<<url("/number");
}

int main(int argc, char *argv[]){
    try{
        cppcms::service srv(argc, argv);
        srv.applications_pool().mount(cppcms::applications_factory<myapp>());
        srv.run();
    }
    catch(exception const &e){
        cerr<<e.what()<<"\n";
    }
}