transcendental-lisp/src/main/LispMain.java

package main;

import interpreter.*;

public class LispMain {

    private LispMain() {}

    public static void main(String[] args) {
        LispInterpreter interpreter = buildInterpreter(args);
        interpreter.interpret();
    }

    private static LispInterpreter buildInterpreter(String[] args) {
        LispInterpreterBuilder builder = LispInterpreterBuilderImpl.getInstance();
        builder.setOutput(System.out);
        builder.setErrorOutput(System.err);
        builder.setTerminationFunction(() -> System.exit(0));
        builder.setErrorTerminationFunction(() -> System.exit(1));
        configureInput(args, builder);

        return builder.build();
    }

    private static void configureInput(String[] args, LispInterpreterBuilder builder) {
        if (args.length > 0)
            builder.useFile(args[0]);
        else {
            builder.setInputName("stdin");
            builder.setInput(System.in);
        }
    }

}