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--- tutorial:mixin_tips [2023/12/18 01:54] – solidblock
+++ tutorial:mixin_tips [2023/12/18 02:06] (current) – solidblock
@@ Line 5: / Line 5: @@
 This is a collection of different tips some might find useful. It's recommended to read the previous articles to understand the tips.
-===== Why make a class abstract? =====
+===== Make abstract classes =====
-==== 1. Prevent instantiation ====
 It's fair to say that you should never instantiate a mixin class, mainly because the class doesn't make sense to java if it isn't used in a mixin environment, and there are other ways to access methods declared in a mixin.
@@ Line 17: / Line 15: @@
 </code>
+===== Make abstract shadow methods =====
-==== 2. Make more elegant shadow methods ====
 If you want to access a unaccessible method or field from your target class into your mixin class, you need to use ''@Shadow'' to make that method/field visible.
@@ Line 37: / Line 34: @@
 Note: this doesn't work with private methods, since you can't have private abstract methods, and hence you need to use the normal one.
-==== 3. Access the ''this'' instance more easily ====
+===== Access the ''this'' instance more easily =====
-In mixin, if you want to access the "this" instance, you have to do a cast inside your mixin class:
+In mixin, if you want to access the "''this''" instance, you have to cast it into ''Object'' first.
 <code java>
@@ Line 100: / Line 97: @@
 These are the same as the static inaccessible inner classes, the only difference is that since they don't have a name, they are declared by appearance order, for example: the anonymous inner class if declared in our previous example class first would be named Outer$1, a second one would be named Outer$2, a third one Outer$3 and so on (the declaration order is on source level).
-** UNDER CONSTRUCTION **
+===== How to mixin to lambdas =====
+Sometimes you want to mixin to lambdas. However, lambda do not have visible names. In this case, remember that **mixin is applied to bytecode instead of source**. Therefore, you can view the bytecode to view lambdas.
+For example, we want to inject the lambda in ''EntitySelectors''. The target code is seen as follows:
+<code java>
+public class EntitySelectorOptions {
+  public static void register() {
+    if (...) {
+      putOption("name", reader -> {
+        // Assume that you want to mixin to here
+        int i = reader.getReader().getCursor();
+        // ...
+      }
+      // ...
+    }
+  }
+}
+</code>
+If you directly injects to ''register'' method, that does not work. Please view the bytecode, and you will find:
+<code java>
+  private static synthetic method_9982(Lnet/minecraft/command/EntitySelectorReader;)V throws com/mojang/brigadier/exceptions/CommandSyntaxException
+   L0
+   // ...
+</code>
+Therefore, the method name of the lambda you want to mixin should be ''method_9982''.
+===== Mixin to those not remapped =====
+If you want to mixin to classes, methods or fields that are not remapped in yarn, such as ''com.mojang.brigadier.StringReader'', you may add ''remap = false'' to avoid potential errors. For example:
+<code java>
+@Mixin(value = StringReader.class, remap = false)
+public abstract class StringReaderMixin { ... }
+</code>
+Another example is:
+<code java>
+@Mixin(EntitySelectorReader.class)
+public abstract class EntitySelectorReaderMixin {
+  @Inject(method = "readTagCharacter", at = @At(value = "INVOKE", target = "Lcom/mojang/brigadier/StringReader;skipWhitespace()V", remap = false)
+  // your injection method ...
+}
+</code>