function readn() {
    const vm = this;
    readline(function (line) {
        const n = parseInt(line, 10);

        if (!n) throw "I/O Error: expecting a number.";

        vm.stack.push(n);
        interpret.call(vm);
    });
    vm.pc++;
}
/**
 * Read a number from input and push it to stack.
 */
Read a number from input and push it to stack.
Read a number from input and push it to stack .
function readn() {
    const vm = this;
    readline(function (line) {
        const n = parseInt(line, 10);
        if (!n) throw "I/O Error: expecting a number.";
        vm.stack.push(n);
        interpret.call(vm);
    });
    vm.pc++;
}
function readn ( ) { const vm = this ; readline ( function ( line ) { const n = parseInt ( line , 10 ) ; if ( ! n ) throw "I/O Error: expecting a number." ; vm . stack . push ( n ) ; interpret . call ( vm ) ; } ) ; vm . pc ++ ; }
Read a number from input and push it to stack.
Read a number from input and push it to stack .