add doc for require() function

src/main/java/zzzank/probejs/docs/LoadClassFn.java

@@ -14,19 +14,40 @@ public class LoadClassFn extends ProbeJSPlugin {
 
     @Override
     public void addGlobals(ScriptDump scriptDump) {
-        val fn = Statements
+        val javaFn = Statements
             .func("java")
             .param("className", Types.STRING)
             .returnType(Types.ANY)
             .build();
 
-        fn.addComment(
-            "@deprecated",
-            "Please use `require(...)` instead." ,
-            "Or just type `$`, and let auto-import call `require()` for you"
+        javaFn.addComment(
+            "@deprecated Please use `require(...)` instead.",
+            "" ,
+            "Or just type `$`, and let auto-import call `require()` for you",
+            "@see require"
         );
 
-        scriptDump.addGlobal("java", fn);
+        val requireFn = Statements
+            .func("require")
+            .param("name", Types.STRING)
+            .returnType(Types.ANY)
+            .build();
+
+        requireFn.addComment(
+            "provided by ProbeJS, to support CommonJS style import/export",
+            "",
+            "You may have already noticed, classes dumped by ProbeJS have `packages/` before their TS module name.",
+            "This is used for differentiating internal classes and variables exported by users.",
+            "",
+            "For `require(\"packages/abcdefg\")` style call, where parameter string starts with `packages/`, ProbeJS",
+            "will try to locate corresponding java class, return located java class, or `undefined` if parameter",
+            "does not match any java class or located Java class is forbidden by KubeJS/Rhino",
+            "",
+            "For `require(\"./abcdefg\")` style call, where parameter string does NOT start with `packages/`, this",
+            "function call will be trimmed before being called. This is used for `export` support."
+        );
+
+        scriptDump.addGlobal("java", javaFn, requireFn);
     }
 
     @Override