Implemented GetVars Visitor

src/main/java/de/hsrm/compiler/Klang/visitors/GetVars.java

@@ -0,0 +1,127 @@
+package de.hsrm.compiler.Klang.visitors;
+
+import java.util.Set;
+
+import de.hsrm.compiler.Klang.nodes.Block;
+import de.hsrm.compiler.Klang.nodes.FunctionDefinition;
+import de.hsrm.compiler.Klang.nodes.Program;
+import de.hsrm.compiler.Klang.nodes.expressions.AdditiveExpression;
+import de.hsrm.compiler.Klang.nodes.expressions.FunctionCall;
+import de.hsrm.compiler.Klang.nodes.expressions.IntegerExpression;
+import de.hsrm.compiler.Klang.nodes.expressions.ModuloExpression;
+import de.hsrm.compiler.Klang.nodes.expressions.MultiplicativeExpression;
+import de.hsrm.compiler.Klang.nodes.expressions.NegateExpression;
+import de.hsrm.compiler.Klang.nodes.expressions.Variable;
+import de.hsrm.compiler.Klang.nodes.statements.IfStatement;
+import de.hsrm.compiler.Klang.nodes.statements.PrintStatement;
+import de.hsrm.compiler.Klang.nodes.statements.ReturnStatement;
+import de.hsrm.compiler.Klang.nodes.statements.VariableAssignment;
+
+class GetVars implements Visitor<Void> {
+
+  public Set<String> vars;
+
+  public GetVars(Set<String> vars) {
+    this.vars = vars;
+  }
+
+  @Override
+  public Void visit(IntegerExpression e) {
+    return null;
+  }
+
+  @Override
+  public Void visit(Variable e) {
+    return null;
+  }
+
+  @Override
+  public Void visit(MultiplicativeExpression e) {
+    e.lhs.welcome(this);
+    e.rhs.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(AdditiveExpression e) {
+    e.lhs.welcome(this);
+    e.rhs.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(NegateExpression e) {
+    e.lhs.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(ModuloExpression e) {
+    e.lhs.welcome(this);
+    e.rhs.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(IfStatement e) {
+    e.cond.welcome(this);
+    e.then.welcome(this);
+    if (e.alt != null) {
+      e.alt.welcome(this);
+    } else if (e.elif != null) {
+      e.elif.welcome(this);
+    }
+    return null;
+  }
+
+  @Override
+  public Void visit(PrintStatement e) {
+    e.expression.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(VariableAssignment e) {
+    vars.add(e.name);
+    e.expression.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(ReturnStatement e) {
+    e.expression.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(Block e) {
+    for (var statement : e.statements) {
+      statement.welcome(this);
+    }
+    return null;
+  }
+
+  @Override
+  public Void visit(FunctionDefinition e) {
+    e.block.welcome(this);
+    return null;
+  }
+
+  @Override
+  public Void visit(FunctionCall e) {
+    for (var expression : e.arguments) {
+      expression.welcome(this);
+    }
+    return null;
+  }
+
+  @Override
+  public Void visit(Program e) {
+    e.expression.welcome(this);
+    for (var func : e.funcs) {
+      func.welcome(this);
+    }
+    return null;
+  }
+
+}