FIX function return interpretation, clean code, ADD README instructions

Author: maxjf1

README.md

@@ -23,3 +23,85 @@ O programa recebem por parâmetro o caminho do arquivo de programa lang a ser ex
 ```bash
 java -jar target/compile-V-0.0.1-jar-with-dependencies.jar caminho/do/programa.lang
 ```
+
+## Exemplo de programa
+
+```c++
+-- Comentário em linha
+
+{-
+
+Comentário em bloco
+
+-}
+
+-- Declaração de estrutura
+data Person {
+    gender :: Char;
+    age :: Int;
+    relatives :: Person[];
+}
+
+-- função principal
+main(){
+
+    read times;                 -- Le inteiro do teclado
+    iterate(times)              -- for primitivo
+        print hello()[0];                -- chamada de função
+
+    me = new Person;            -- Instancia estrutura
+    me.age = 24;                -- atribuição de propriedade
+    me.gender = 'm';
+    me.relatives = new Person[10];
+    me.relatives[0] = new Person;
+    me.relatives[0].age = 40;
+    me.relatives[0].gender = 'f';
+
+    print fibonacci(9)[0];  -- get return of a function
+    ln();
+
+    divide(10, 3)<result, resto>;
+    print result;
+    ln();
+    print resto;
+    ln();
+
+}
+
+fibonacci(n :: Int) : Int
+{
+    if (n < 1)
+        return n;
+    if (n == 1)
+        return n;
+    return fibonacci(n-1)[0] + fibonacci(n-2)[0];
+}
+
+divide(a :: Int, b :: Int) : Int, Int {
+    return a / b, a % b;
+}
+-- sobrecarga
+divide(a :: Float, b :: Float) : Float, Float {
+    return a / b, a % b;
+}
+
+ln(){ print '\n'; }
+
+hello() : Char[] {
+    message = new Char[13];     -- Instancia array
+    message[0] = 'h';
+    message[1] = 'e';
+    message[2] = 'l';
+    message[3] = 'l';
+    message[4] = 'o';
+    message[5] = ' ';
+    message[6] = 'w';
+    message[7] = 'o';
+    message[8] = 'r';
+    message[9] = 'l';
+    message[10] = 'd';
+    message[11] = '!';
+    message[12] = '\n';
+    return message;
+}
+```

src/main/java/lexlang/LangInterpreter.java

@@ -25,7 +25,6 @@ public class LangInterpreter extends LexLangBaseVisitor<Value> {
     FunctionManager functionManager;
 
     Boolean returnCalled = false;
-    List<Value> returnValues = null;
 
     public LangInterpreter(SemanticAnalyzer analyzer) {
         this.functionManager = analyzer.getFuncManager();
@@ -156,56 +155,45 @@ public Value visitInstancePexp(LexLangParser.InstancePexpContext ctx) {
         }
         if (List.of("Int", "Char", "Bool", "Float").contains(type))
             return new Value(null);
-//        if (!dataTypes.containsKey(type))
-//            throw new LangException("Data '" + type + "' not found");
         return new Value(new Data(dataTypes.get(type)));
     }
 
     // functions
-//    @Override
-//    public Value visitFunc(LexLangParser.FuncContext ctx) {
-//        functionManager.addFunction(ctx);
-//        return Value.VOID;
-//    }
 
     @Override
     public Value visitFuncCmd(LexLangParser.FuncCmdContext ctx) {
         String name = ctx.ID().getText();
-        Value ret = runFunction(name, ctx.exps());
-        for (int i = 0; i < ctx.lvalue().size(); i++) {
-            resolveVariable(ctx.lvalue(i), returnValues.get(i));
+        Value returnValue = runFunction(name, ctx.exps());
+        if(ctx.lvalue().size() > 0) {
+            ArrayList<Value> returnList = (ArrayList<Value>) returnValue.getPrimitive();
+            for (int i = 0; i < ctx.lvalue().size(); i++)
+                resolveVariable(ctx.lvalue(i), returnList.get(i));
         }
-        returnValues = null;
-        return ret;
+        return returnValue;
     }
 
     @Override
     public Value visitFuncCallPexp(LexLangParser.FuncCallPexpContext ctx) {
         String name = ctx.ID().getText();
-        Value result = runFunction(name, ctx.exps());
+        Value returnValue = runFunction(name, ctx.exps());
+        ArrayList<Value> returnList = (ArrayList<Value>) returnValue.getPrimitive();
         if (ctx.exp() != null) {
             int i = visit(ctx.exp()).getInt();
-//            if (returnValues == null)
-//                throw new LangException("Function '" + name +
-//                        "' doesn't returns arguments, tried to access argument [" + i + ']');
-//            if (i >= returnValues.size())
-//                throw new LangException("Function '" + name +
-//                        "' only returns " + returnValues.size() +
-//                        " arguments, tried to access argument [" + i + ']');
-            result = returnValues.get(i);
+            returnValue = returnList.get(i);
         }
-        returnValues = null;
-        return result;
+        else returnValue = returnList.get(0);
+        return returnValue;
     }
 
     @Override
     public Value visitReturnCmd(LexLangParser.ReturnCmdContext ctx) {
-        this.returnValues = new ArrayList<>();
+        ArrayList<Value> ret = new ArrayList<Value>();
         for (LexLangParser.ExpContext expContext : ctx.exp()) {
-            this.returnValues.add(visit(expContext));
+            ret.add(visit(expContext));
+
         }
         this.returnCalled = true;
-        return this.returnValues.get(0);
+        return new Value(ret);
     }
 
     // variables
@@ -386,7 +374,7 @@ public Value visitReadCmd(LexLangParser.ReadCmdContext ctx) {
         String response = reader.nextLine();
         int val;
         try {
-            val = Integer.parseInt(response);
+            val = Integer.valueOf(response);
         } catch (Exception e) {
             throw new LangException("Read error: 'Int' expected, received '" + response + "'", ctx);
         }

src/main/java/lexlang/Value.java

@@ -47,6 +47,10 @@ public ArrayValue getArray() {
         return (ArrayValue) primitive;
     }
 
+    public Object getPrimitive() {
+        return primitive;
+    }
+
     @Override
     public boolean equals(Object o) {
         if (primitive == o) return true;