Any suggestions you can give for this code?:

import std.conv : to, ConvException;
import std.string : strip;
import std.stdio : writeln, write, readln;
import std.random : uniform;

enum GiveUpCode = 500;

int generateNumber() {
    return uniform(1, 100);
}

void printMessage(string message) {
    writeln(message);
}

void gameStart() {
    int number = generateNumber();
    int tries = 0;
    int guess;

    do {
        write("Guess a number between 1 and 100: ");
        try {
            guess = readln().strip().to!int;

            if (guess == GiveUpCode) {
                printMessage("You gave up! The number was: " ~ to!string(number) ~ ". " ~ (tries == 0 ? "Don't give up that easy!" : "But nice try, you can try again if you like!"));
                return;
            }

            if (guess < 1 || guess > 100) {
                printMessage("Please enter a number between 1 and 100 or enter '" ~ to!string(GiveUpCode) ~ "' to exit the game. Try again, please.");
                continue;
            }
        } catch (ConvException e) {
            printMessage("Do not enter letters, signs, no blank spaces, or something else that isn't a number! Try again!");
            continue;
        }

        tries++;

        if (guess < number) {
            printMessage("Too low. Try again.");
        } else if (guess > number) {
            printMessage("Too high. Try again.");
        } else {
            printMessage("Congratulations! You guessed the number correctly in " ~ to!string(tries) ~ (tries == 1 ? " attempt!" : " tries!"));
        }
    } while (guess != number);

    printMessage("Thanks for playing!");
}

int main() {
    printMessage("Welcome to the number guessing game! If you guess the number correctly, you win!.\nIf you can't guess the number, you can enter '" ~ to!string(GiveUpCode) ~ "' to exit the game.");
    gameStart();
    return 0;
}