Mojang
[Suggestion] Optional Arguments
Ok this is a bit rough to start.
When commands in Minecraft are created, you have either 2 ways of creating commands that are executed. Either implement every single execution itself. (If you have 5 optional parameters that's getting annoying really quickly) Or you implement a CommandContext Wrapper that basically does this:
public boolean hasValue(String id, Class<?> type)
{
try
{
return source.getArgument(id, type) != null;
}
catch(Exception e)
{
return false;
}
}
public <T> T getOrDefault(String id, Class<T> type, T defaultValue)
{
try
{
return source.getArgument(id, type);
}
catch(Exception e)
{
}
return defaultValue;
}
It would be nice if you could check if arguments have been defined or allow to getOrDefault. This is mainly there to reduce code. Implementing everything 5 times. Even if Lambdas are being used that call a helper function that basically does the same. Instead this could look a lot cleaner.
Here is a example with my CommandBuilder & Command Wrapper
public static CommandBuilder createGenStart()
{
CommandBuilder builder = new CommandBuilder("gen");
//Normal Gen
Command<CommandSource> radius = GenCommand::executeRadius;
builder.addLiteral("radius");
builder.addArgument("Task Name", StringArgumentType.word());
builder.addArgument("Shape", StringArgumentType.word(), GenCommand::listShape);
builder.addArgument("Center", ColumnPosArgument.columnPos(), CenterArgument::listSimpleSuggestion);
builder.addArgument("Radius", IntegerArgumentType.integer(1, 25000), radius);
builder.addArgument("Dimension", DimensionArgument.getDimension(), radius); //Optional
builder.addArgument("Generation Type", StringArgumentType.word(), GenCommand::listSuggestions, radius).popTop(); //PopTop basically goes down the logic tree allowing to make a new branch. A single/multi pop exists too.
Command<CommandSource> expansion = GenCommand::executeExpansion;
builder.addLiteral("expansion");
builder.addArgument("Task Name", StringArgumentType.word());
builder.addArgument("Shape", StringArgumentType.word(), GenCommand::listShape);
builder.addArgument("Center", ColumnPosArgument.columnPos(), CenterArgument::listSimpleSuggestion);
builder.addArgument("Min Radius", IntegerArgumentType.integer(1));
builder.addArgument("Max Radius", IntegerArgumentType.integer(1), expansion);
builder.addArgument("Dimension", DimensionArgument.getDimension(), expansion);
builder.addArgument("Generation Type", StringArgumentType.word(), GenCommand::listSuggestions, expansion).popTop();
return builder;
}
private static int executeRadius(CommandContext<CommandSource> source)
{
CommandWrapper wrapper = new CommandWrapper(source);
String name = wrapper.get("Task Name", String.class);
GenShape shape = wrapper.hasValue("Shape", String.class) ? GenShape.valueOf(wrapper.get("Shape", String.class)) : wrapper.get("Shape", GenShape.class);
BlockPos center = CenterArgument.getVanillaBlockPos(wrapper.get("Center", ILocationArgument.class), source.getSource());
int radius = wrapper.get("Radius", Integer.class);
ResourceLocation dimension = wrapper.getOrDefault("Dimension", ResourceLocation.class, wrapper.getSource().getWorld().getDimensionKey().getLocation());
return 0;
}
The Reason for hasValue is used for the GenShape is a example. What if the software that the CommandContext uses only exists on 1 side. It can detect if a single side exists, or if dual sided implementation is present. Or in modding terms: ServerOnly Mods.
This is how I would implement it. If you want I can make it a offical PR, or you can just grab the implementation. Reference Code: https://github.com/Mojang/brigadier/blob/master/src/main/java/com/mojang/brigadier/context/CommandContext.java#L81
public <V> boolean hasArgument(final String name, final Class<V> clazz) {
final ParsedArgument<S, ?> argument = arguments.get(name);
if (argument == null) {
return false;
}
final Object result = argument.getResult();
if (PRIMITIVE_TO_WRAPPER.getOrDefault(clazz, clazz).isAssignableFrom(result.getClass())) {
return true;
} else {
return false;
}
}
public <V> V getArgument(final String name, final Class<V> clazz, V defaultValue) {
final ParsedArgument<S, ?> argument = arguments.get(name);
if (argument == null) {
return defaultValue;
}
final Object result = argument.getResult();
if (PRIMITIVE_TO_WRAPPER.getOrDefault(clazz, clazz).isAssignableFrom(result.getClass())) {
return (V) result;
} else {
return defaultValue;
}
}
@Gamebuster19901 the point is: You are required to write duplicated implementations for every single Optional argument. Or write a specific handler that redirects to a function where you insert the default argument. Causing for a LOT of code duplication. 1 function where you handle everything, including Default Arguments is a lot simpler to deal with and also a lot easier to read.
Just look at my code example that I have done and replicate it and look how much worse it looks and is to maintain if you don't have these features.
I dunno what you think but if you have 8 versions to maintain and have to do fixes for one or two functions that have to interact with that it just gets bad. This is why i have added a wrapper for myself that allows for this kind of functionality, to make this possible.
And it is quite sad that Mojang doesn't see the Benefit of such a function that doesn't have ANY downsides.
Honestly this is just a very tiny QoL change that is "Optional" yet mojang hasn't included. I don't expect Mojang to ever include this.
To be honest. It is probably not going to be implemented however if it does, it will be a great change.