...wyrd_compiler

22 files changed, 581 insertions, 181 deletions

diff --git a/data/examples/monster_battle/in_your_room.fate b/data/examples/monster_battle/in_your_room.fate
index 892c680..8f30a00 100644
--- a/data/examples/monster_battle/in_your_room.fate
+++ b/data/examples/monster_battle/in_your_room.fate
@@ -52,7 +52,7 @@
                Oh! You found something!
             )
          )
-         (imacro get_item (ref (var potion)))
+         (macro get_item (ref (var potion)))
       )
       (text_effect narrator
          No, you don't find anything.
@@ -70,7 +70,7 @@
    (text_effect narrator
       It's a monster-holder! There's a note, too.
    )
-   (imacro generate_random_creature (var player.creature))
+   (macro generate_random_creature (var player.creature))
    (event pause)
    (text_effect note_reading
       Hey sleepyhead. I couldn't wake you up for your big day, but lucky you,
diff --git a/src/core/src/tonkadur/Main.java b/src/core/src/tonkadur/Main.java
index 23666dd..4dabacb 100644
--- a/src/core/src/tonkadur/Main.java
+++ b/src/core/src/tonkadur/Main.java
@@ -4,8 +4,6 @@ import java.io.IOException;
 
 import tonkadur.parser.Context;
 
-import tonkadur.fate.v1.lang.World;
-
 import tonkadur.fate.v1.Utils;
 
 public class Main
@@ -15,23 +13,42 @@ public class Main
 
    public static void main (final String[] args)
    {
-      final World world;
+      final tonkadur.fate.v1.lang.World fate_world;
+      final tonkadur.wyrd.v1.lang.World wyrd_world;
       final Context context;
 
-      world = new World();
+      fate_world = new tonkadur.fate.v1.lang.World();
       context = Context.build(args[0]);
 
       try
       {
-         Utils.add_file_content(context.get_current_file(), context, world);
+         Utils.add_file_content
+         (
+            context.get_current_file(),
+            context,
+            fate_world
+         );
 
          System.out.println("Parsing completed.");
-         System.out.println(world.toString());
+         System.out.println(fate_world.toString());
       }
       catch (final Exception e)
       {
          System.err.println("Parsing failed.");
-         System.err.println(world.toString());
+         System.err.println(fate_world.toString());
+         e.printStackTrace();
+      }
+
+      try
+      {
+         wyrd_world =
+            tonkadur.wyrd.v1.compiler.fate.v1.Compiler.compile(fate_world);
+
+         System.out.println("Compilation completed.");
+      }
+      catch (final Throwable e)
+      {
+         System.err.println("Compilation failed.");
          e.printStackTrace();
       }
    }
diff --git a/src/core/src/tonkadur/fate/v1/lang/computation/IfElseValue.java b/src/core/src/tonkadur/fate/v1/lang/computation/IfElseValue.java
index 63adfb6..5288163 100644
--- a/src/core/src/tonkadur/fate/v1/lang/computation/IfElseValue.java
+++ b/src/core/src/tonkadur/fate/v1/lang/computation/IfElseValue.java
@@ -123,6 +123,22 @@ public class IfElseValue extends Computation
    }
 
    /**** Accessors ************************************************************/
+
+   public Computation get_condition ()
+   {
+      return condition;
+   }
+
+   public Computation get_if_true ()
+   {
+      return if_true;
+   }
+
+   public Computation get_if_false ()
+   {
+      return if_false;
+   }
+
    @Override
    public void get_visited_by (final ComputationVisitor cv)
    throws Throwable
diff --git a/src/core/src/tonkadur/fate/v1/lang/computation/Operation.java b/src/core/src/tonkadur/fate/v1/lang/computation/Operation.java
index dfbfcb3..d67fa1d 100644
--- a/src/core/src/tonkadur/fate/v1/lang/computation/Operation.java
+++ b/src/core/src/tonkadur/fate/v1/lang/computation/Operation.java
@@ -175,4 +175,14 @@ public class Operation extends Computation
    {
       cv.visit_operation(this);
    }
+
+   public Operator get_operator ()
+   {
+      return operator;
+   }
+
+   public List<Computation> get_operands ()
+   {
+      return operands;
+   }
 }
diff --git a/src/core/src/tonkadur/fate/v1/lang/computation/RefOperator.java b/src/core/src/tonkadur/fate/v1/lang/computation/RefOperator.java
index 49f3ef6..54cdaad 100644
--- a/src/core/src/tonkadur/fate/v1/lang/computation/RefOperator.java
+++ b/src/core/src/tonkadur/fate/v1/lang/computation/RefOperator.java
@@ -28,8 +28,6 @@ public class RefOperator extends Computation
    /***************************************************************************/
    /**** PUBLIC ***************************************************************/
    /***************************************************************************/
-   /**** Constructors *********************************************************/
-
    /**** Accessors ************************************************************/
    @Override
    public void get_visited_by (final ComputationVisitor cv)
@@ -38,6 +36,11 @@ public class RefOperator extends Computation
       cv.visit_ref_operator(this);
    }
 
+   public Reference get_target ()
+   {
+      return referred;
+   }
+
    /**** Misc. ****************************************************************/
    @Override
    public String toString ()
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/ComputationCompiler.java b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/ComputationCompiler.java
index 1cc3af8..52d92bc 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/ComputationCompiler.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/ComputationCompiler.java
@@ -1,5 +1,6 @@
 package tonkadur.wyrd.v1.compiler.fate.v1;
 
+import java.util.Collections;
 import java.util.List;
 import java.util.ArrayList;
 
@@ -8,8 +9,14 @@ import tonkadur.error.Error;
 import tonkadur.wyrd.v1.lang.meta.Computation;
 import tonkadur.wyrd.v1.lang.meta.Instruction;
 
-import tonkadur.wyrd.v1.lang.computation.Ref;
-import tonkadur.wyrd.v1.lang.computation.ValueOf;
+import tonkadur.wyrd.v1.lang.type.Type;
+
+import tonkadur.wyrd.v1.lang.instruction.SetValue;
+
+import tonkadur.wyrd.v1.compiler.util.IfElse;
+
+import tonkadur.wyrd.v1.lang.computation.*;
+
 
 import tonkadur.wyrd.v1.lang.World;
 
@@ -17,30 +24,38 @@ public class ComputationCompiler
 implements tonkadur.fate.v1.lang.meta.ComputationVisitor
 {
    protected final Compiler compiler;
-   protected final List<Instruction> pre_computation_instructions;
-   protected final List<Ref> allocated_variables;
-   protected final boolean expect_ref;
+   protected final List<Instruction> init_instructions;
+   protected final List<Ref> reserved_variables;
+   protected boolean instructions_were_generated;
    protected Computation result_as_computation;
    protected Ref result_as_ref;
 
-   public ComputationCompiler
-   (
-      final Compiler compiler,
-      final boolean expect_ref
-   )
+   public ComputationCompiler (final Compiler compiler)
    {
       this.compiler = compiler;
-      this.expect_ref = expect_ref;
 
-      allocated_variables = new ArrayList<Ref>();
-      pre_computation_instructions = new ArrayList<Instruction>();
+      reserved_variables = new ArrayList<Ref>();
+      init_instructions = new ArrayList<Instruction>();
       result_as_ref = null;
       result_as_computation = null;
+      instructions_were_generated = false;
+   }
+
+   public boolean has_init ()
+   {
+      return !init_instructions.isEmpty();
    }
 
    public Instruction get_init ()
    {
-      return compiler.assembler().merge(pre_computation_instructions);
+      instructions_were_generated = true;
+
+      if (init_instructions.isEmpty())
+      {
+         return null;
+      }
+
+      return compiler.assembler().merge(init_instructions);
    }
 
    public Computation get_computation ()
@@ -59,37 +74,52 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
 
    public Ref get_ref ()
    {
-      if ((result_as_ref == null) && (result_as_computation != null))
-      {
-         generate_ref();
-      }
-
       return result_as_ref;
    }
 
-   protected void generate_ref ()
+   public void generate_ref ()
    {
-      final Ref result;
+      if ((!instructions_were_generated) && (result_as_ref == null))
+      {
+         final Ref result;
+
+         result = reserve(result_as_computation.get_type());
 
-      result =
-         compiler.anonymous_variables().reserve
+         init_instructions.add
          (
-            result_as_computation.get_type()
+            new SetValue(result, result_as_computation)
          );
 
-      allocated_variables.add(result);
 
-      result_as_ref = result;
+         result_as_ref = result;
+      }
    }
 
    public void release_variables ()
    {
-      for (final Ref ref: allocated_variables)
+      for (final Ref ref: reserved_variables)
       {
          compiler.anonymous_variables().release(ref);
       }
    }
 
+   protected void assimilate (final ComputationCompiler cc)
+   {
+      init_instructions.addAll(cc.init_instructions);
+      reserved_variables.addAll(cc.reserved_variables);
+   }
+
+   protected Ref reserve (final Type t)
+   {
+      final Ref result;
+
+      result = compiler.anonymous_variables().reserve(t);
+
+      reserved_variables.add(result);
+
+      return result;
+   }
+
    @Override
    public void visit_at_reference
    (
@@ -97,7 +127,27 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final ComputationCompiler n_cc;
+
+      n_cc = new ComputationCompiler(compiler);
+
+      n.get_parent().get_visited_by(n_cc);
+
+      assimilate(n_cc);
+
+      result_as_ref =
+         new Ref
+         (
+            n_cc.get_computation(),
+            TypeCompiler.compile
+            (
+               compiler,
+               (
+                  (tonkadur.fate.v1.lang.type.RefType)
+                     n.get_parent().get_type()
+               ).get_referenced_type()
+            )
+         );
    }
 
    @Override
@@ -127,7 +177,12 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      result_as_computation =
+         new Constant
+         (
+            TypeCompiler.compile(compiler, n.get_type()),
+            n.get_value_as_string()
+         );
    }
 
    @Override
@@ -147,7 +202,28 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final ComputationCompiler n_cc;
+
+      n_cc = new ComputationCompiler(compiler);
+
+      n.get_parent().get_visited_by(n_cc);
+
+      assimilate(n_cc);
+
+      result_as_ref =
+         new RelativeRef
+         (
+            n_cc.get_ref(),
+            new Constant(Type.STRING, n.get_field_name()),
+            TypeCompiler.compile
+            (
+               compiler,
+               (
+                  (tonkadur.fate.v1.lang.type.RefType)
+                     n.get_parent().get_type()
+               ).get_referenced_type()
+            )
+         );
    }
 
    @Override
@@ -157,7 +233,97 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final ComputationCompiler cond_cc, if_true_cc, if_false_cc;
+
+      cond_cc = new ComputationCompiler(compiler);
+      if_true_cc = new ComputationCompiler(compiler);
+      if_false_cc = new ComputationCompiler(compiler);
+
+      n.get_condition().get_visited_by(cond_cc);
+      n.get_if_true().get_visited_by(if_true_cc);
+      n.get_if_false().get_visited_by(if_false_cc);
+
+      if (if_true_cc.has_init() || if_false_cc.has_init())
+      {
+         /*
+          * Unsafe ifelse computation: at least one of the branches needs to
+          * use instructions with values *before* the condition has been
+          * checked. This results in non-lazy evaluation, and is dangerous:
+          * the condition might be a test to ensure that the computations of the
+          * chosen branch are legal. In such cases, performing the potentially
+          * illegal branch's instructions is likely to result in a runtime error
+          * on the interpreter.
+          *
+          * Instead, we just convert the ifelse into an instruction-based
+          * equivalent and store the result in an anonymous variable to be used
+          * here.
+          */
+         final Ref if_else_result;
+         final List<Instruction> if_true_branch;
+         final List<Instruction> if_false_branch;
+
+         if_else_result = reserve(if_true_cc.get_computation().get_type());
+
+         if_true_branch = new ArrayList<Instruction>();
+         if_false_branch = new ArrayList<Instruction>();
+
+         if (if_true_cc.has_init())
+         {
+            if_true_branch.add(if_true_cc.get_init());
+         }
+
+         if (if_false_cc.has_init())
+         {
+            if_false_branch.add(if_false_cc.get_init());
+         }
+
+         if_true_branch.add
+         (
+            new SetValue(if_else_result, if_true_cc.get_computation())
+         );
+
+         if_false_branch.add
+         (
+            new SetValue(if_else_result, if_false_cc.get_computation())
+         );
+
+         if (cond_cc.has_init())
+         {
+            init_instructions.add(cond_cc.get_init());
+         }
+
+         init_instructions.add
+         (
+            IfElse.generate
+            (
+               compiler.anonymous_variables(),
+               compiler.assembler(),
+               cond_cc.get_computation(),
+               compiler.assembler().merge(if_true_branch),
+               compiler.assembler().merge(if_false_branch)
+            )
+         );
+
+         reserved_variables.addAll(cond_cc.reserved_variables);
+         reserved_variables.addAll(if_true_cc.reserved_variables);
+         reserved_variables.addAll(if_false_cc.reserved_variables);
+
+         result_as_computation = new ValueOf(if_else_result);
+      }
+      else
+      {
+         assimilate(cond_cc);
+         assimilate(if_true_cc);
+         assimilate(if_false_cc);
+
+         result_as_computation =
+            new IfElseComputation
+            (
+               cond_cc.get_computation(),
+               if_true_cc.get_computation(),
+               if_false_cc.get_computation()
+            );
+      }
    }
 
    @Override
@@ -187,7 +353,7 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      result_as_computation = new Newline();
    }
 
    @Override
@@ -197,7 +363,8 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      /* TODO */
+      result_as_computation = new Constant(Type.INT, "0");
    }
 
    @Override
@@ -207,7 +374,28 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final List<Computation> content;
+
+      content = new ArrayList<Computation>();
+
+      for
+      (
+         final tonkadur.fate.v1.lang.meta.Computation fate_content:
+            n.get_content()
+      )
+      {
+         final ComputationCompiler content_cc;
+
+         content_cc = new ComputationCompiler(compiler);
+
+         fate_content.get_visited_by(content_cc);
+
+         assimilate(content_cc);
+
+         content.add(content_cc.get_computation());
+      }
+
+      result_as_computation = new RichText(content);
    }
 
    @Override
@@ -217,7 +405,7 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      result_as_ref = compiler.macros().get_parameter_ref(n.get_name());
    }
 
    @Override
@@ -227,7 +415,15 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final ComputationCompiler n_cc;
+
+      n_cc = new ComputationCompiler(compiler);
+
+      n.get_target().get_visited_by(n_cc);
+
+      assimilate(n_cc);
+
+      result_as_computation = n_cc.result_as_ref;
    }
 
    @Override
@@ -237,7 +433,40 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      final ComputationCompiler text_cc;
+      final List<Computation> parameters;
+
+      text_cc = new ComputationCompiler(compiler);
+      parameters = new ArrayList<Computation>();
+
+      n.get_text().get_visited_by(text_cc);
+
+      assimilate(text_cc);
+
+      for
+      (
+         final tonkadur.fate.v1.lang.meta.Computation fate_param:
+            n.get_parameters()
+      )
+      {
+         final ComputationCompiler param_cc;
+
+         param_cc = new ComputationCompiler(compiler);
+
+         fate_param.get_visited_by(param_cc);
+
+         assimilate(param_cc);
+
+         parameters.add(param_cc.get_computation());
+      }
+
+      result_as_computation =
+         new AddRichTextEffect
+         (
+            n.get_effect().get_name(),
+            parameters,
+            Collections.singletonList(text_cc.get_computation())
+         );
    }
 
    @Override
@@ -247,7 +476,10 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      n.get_value().get_visited_by(this);
+
+      result_as_computation =
+         new RichText(Collections.singletonList(result_as_computation));
    }
 
    @Override
@@ -257,6 +489,9 @@ implements tonkadur.fate.v1.lang.meta.ComputationVisitor
    )
    throws Throwable
    {
-      /* TODO: implement */
+      result_as_ref =
+         compiler.world().get_variable(n.get_variable().get_name()).get_ref();
+
+      result_as_computation = new ValueOf(result_as_ref);
    }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
index b4038dd..8ed0c87 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/fate/v1/InstructionCompiler.java
@@ -100,17 +100,27 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final Type element_type;
       final Computation value_of_element, value_of_collection_size;
 
-      element_compiler = new ComputationCompiler(compiler, false);
+      element_compiler = new ComputationCompiler(compiler);
       ae.get_element().get_visited_by(element_compiler);
-      result.add(element_compiler.get_init());
+
+      if (element_compiler.has_init())
+      {
+         result.add(element_compiler.get_init());
+      }
+
       element_type = element_compiler.get_computation().get_type();
       element = compiler.anonymous_variables().reserve(element_type);
       result.add(new SetValue(element, element_compiler.get_computation()));
       element_compiler.release_variables();
 
-      reference_compiler = new ComputationCompiler(compiler, true);
+      reference_compiler = new ComputationCompiler(compiler);
       ae.get_collection().get_visited_by(reference_compiler);
-      result.add(reference_compiler.get_init());
+
+      if (reference_compiler.has_init())
+      {
+         result.add(reference_compiler.get_init());
+      }
+
       collection = reference_compiler.get_ref();
 
       element_found = compiler.anonymous_variables().reserve(Type.BOOLEAN);
@@ -185,18 +195,26 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final Ref collection_as_ref;
       final ComputationCompiler element_compiler, reference_compiler;
 
-      element_compiler = new ComputationCompiler(compiler, false);
+      element_compiler = new ComputationCompiler(compiler);
 
       ae.get_element().get_visited_by(element_compiler);
 
-      reference_compiler = new ComputationCompiler(compiler, true);
+      reference_compiler = new ComputationCompiler(compiler);
 
       ae.get_collection().get_visited_by(reference_compiler);
 
       collection_as_ref = reference_compiler.get_ref();
 
-      result.add(reference_compiler.get_init());
-      result.add(element_compiler.get_init());
+      if (reference_compiler.has_init())
+      {
+         result.add(reference_compiler.get_init());
+      }
+
+      if (element_compiler.has_init())
+      {
+         result.add(element_compiler.get_init());
+      }
+
       result.add
       (
          new SetValue
@@ -204,13 +222,10 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
             new RelativeRef
             (
                collection_as_ref,
-               Collections.singletonList
+               new Cast
                (
-                  new Cast
-                  (
-                     new Size(collection_as_ref),
-                     Type.STRING
-                  )
+                  new Size(collection_as_ref),
+                  Type.STRING
                ),
                element_compiler.get_computation().get_type()
             ),
@@ -266,11 +281,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
        */
       final ComputationCompiler cc;
 
-      cc = new ComputationCompiler(compiler, false);
+      cc = new ComputationCompiler(compiler);
 
       a.get_condition().get_visited_by(cc);
 
-      result.add(cc.get_init());
+      if (cc.has_init())
+      {
+         result.add(cc.get_init());
+      }
+
       result.add(new Assert(cc.get_computation()));
 
       cc.release_variables();
@@ -288,13 +307,17 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final ComputationCompiler reference_compiler;
       final Ref collection_ref;
 
-      reference_compiler = new ComputationCompiler(compiler, true);
+      reference_compiler = new ComputationCompiler(compiler);
 
       c.get_collection().get_visited_by(reference_compiler);
 
       collection_ref = reference_compiler.get_ref();
 
-      result.add(reference_compiler.get_init());
+      if (reference_compiler.has_init())
+      {
+         result.add(reference_compiler.get_init());
+      }
+
       result.add
       (
          Clear.generate
@@ -358,11 +381,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
          current_else_branch = new ArrayList<Instruction>();
 
          ic = new InstructionCompiler(compiler);
-         cc = new ComputationCompiler(compiler, false);
+         cc = new ComputationCompiler(compiler);
 
          branch.get_car().get_visited_by(cc);
 
-         previous_else_branch.add(cc.get_init());
+         if (cc.has_init())
+         {
+            previous_else_branch.add(cc.get_init());
+         }
+
          previous_else_branch.add
          (
             IfElse.generate
@@ -401,12 +428,16 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
        */
       final ComputationCompiler cc;
 
-      cc = new ComputationCompiler(compiler, false);
+      cc = new ComputationCompiler(compiler);
 
       n.get_content().get_visited_by(cc);
 
-      result.add(cc.get_init());
-      result.add(new Display(Collections.singletonList(cc.get_computation())));
+      if (cc.has_init())
+      {
+         result.add(cc.get_init());
+      }
+
+      result.add(new Display(cc.get_computation()));
 
       cc.release_variables();
    }
@@ -437,11 +468,14 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       {
          final ComputationCompiler cc;
 
-         cc = new ComputationCompiler(compiler, false);
+         cc = new ComputationCompiler(compiler);
 
          fate_computation.get_visited_by(cc);
 
-         result.add(cc.get_init());
+         if (cc.has_init())
+         {
+            result.add(cc.get_init());
+         }
 
          cc_list.add(cc);
          parameters.add(cc.get_computation());
@@ -471,7 +505,7 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final InstructionCompiler if_true_ic;
       final InstructionCompiler if_false_ic;
 
-      cc = new ComputationCompiler(compiler, false);
+      cc = new ComputationCompiler(compiler);
       if_true_ic = new InstructionCompiler(compiler);
       if_false_ic = new InstructionCompiler(compiler);
 
@@ -479,7 +513,11 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       n.get_if_true().get_visited_by(if_true_ic);
       n.get_if_false().get_visited_by(if_false_ic);
 
-      result.add(cc.get_init());
+      if (cc.has_init())
+      {
+         result.add(cc.get_init());
+      }
+
       result.add
       (
          IfElse.generate
@@ -510,13 +548,17 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final ComputationCompiler cc;
       final InstructionCompiler if_true_ic;
 
-      cc = new ComputationCompiler(compiler, false);
+      cc = new ComputationCompiler(compiler);
       if_true_ic = new InstructionCompiler(compiler);
 
       n.get_condition().get_visited_by(cc);
       n.get_if_true().get_visited_by(if_true_ic);
 
-      result.add(cc.get_init());
+      if (cc.has_init())
+      {
+         result.add(cc.get_init());
+      }
+
       result.add
       (
          If.generate
@@ -585,11 +627,14 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       {
          final ComputationCompiler cc;
 
-         cc = new ComputationCompiler(compiler, true);
+         cc = new ComputationCompiler(compiler);
 
          fate_computation.get_visited_by(cc);
 
-         result.add(cc.get_init());
+         if (cc.has_init())
+         {
+            result.add(cc.get_init());
+         }
 
          cc_list.add(cc);
          parameters.add(cc.get_ref());
@@ -620,12 +665,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final ComputationCompiler cc;
       final InstructionCompiler ic;
 
-      cc = new ComputationCompiler(compiler, false);
+      cc = new ComputationCompiler(compiler);
       ic = new InstructionCompiler(compiler);
 
       n.get_text().get_visited_by(cc);
 
-      result.add(cc.get_init());
+      if (cc.has_init())
+      {
+         result.add(cc.get_init());
+      }
 
       for
       (
@@ -710,8 +758,8 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final ComputationCompiler elem_cc, collection_cc;
       final Ref elem, collection_size, collection;
 
-      elem_cc = new ComputationCompiler(compiler, false);
-      collection_cc = new ComputationCompiler(compiler, true);
+      elem_cc = new ComputationCompiler(compiler);
+      collection_cc = new ComputationCompiler(compiler);
 
       elem =
          compiler.anonymous_variables().reserve
@@ -724,8 +772,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       n.get_element().get_visited_by(elem_cc);
       n.get_collection().get_visited_by(collection_cc);
 
-      result.add(elem_cc.get_init());
-      result.add(collection_cc.get_init());
+      if (elem_cc.has_init())
+      {
+         result.add(elem_cc.get_init());
+      }
+
+      if (collection_cc.has_init())
+      {
+         result.add(collection_cc.get_init());
+      }
 
       collection = collection_cc.get_ref();
 
@@ -856,8 +911,8 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       final Ref collection;
       final Computation value_of_collection_size;
 
-      elem_cc = new ComputationCompiler(compiler, false);
-      collection_cc = new ComputationCompiler(compiler, true);
+      elem_cc = new ComputationCompiler(compiler);
+      collection_cc = new ComputationCompiler(compiler);
 
       elem =
          compiler.anonymous_variables().reserve
@@ -872,8 +927,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       n.get_element().get_visited_by(elem_cc);
       n.get_collection().get_visited_by(collection_cc);
 
-      result.add(elem_cc.get_init());
-      result.add(collection_cc.get_init());
+      if (elem_cc.has_init())
+      {
+         result.add(elem_cc.get_init());
+      }
+
+      if (collection_cc.has_init())
+      {
+         result.add(collection_cc.get_init());
+      }
 
       collection = collection_cc.get_ref();
 
@@ -985,14 +1047,22 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
        */
       final ComputationCompiler value_cc, ref_cc;
 
-      value_cc = new ComputationCompiler(compiler, false);
-      ref_cc = new ComputationCompiler(compiler, true);
+      value_cc = new ComputationCompiler(compiler);
+      ref_cc = new ComputationCompiler(compiler);
 
       n.get_value().get_visited_by(value_cc);
-      result.add(value_cc.get_init());
+
+      if (value_cc.has_init())
+      {
+         result.add(value_cc.get_init());
+      }
 
       n.get_reference().get_visited_by(ref_cc);
-      result.add(ref_cc.get_init());
+
+      if (ref_cc.has_init())
+      {
+         result.add(ref_cc.get_init());
+      }
 
       result.add
       (
@@ -1002,4 +1072,15 @@ implements tonkadur.fate.v1.lang.meta.InstructionVisitor
       value_cc.release_variables();
       ref_cc.release_variables();
    }
+
+   /*
+    * TODO: Be careful about compiling Fate's loop operators:
+    *    You can't do:
+    *       condition.get_visited_by(ComputationCompiler);
+    *       result.add(ComputationCompiler.get_init();
+    *       result.add(While.generate(...));
+    *
+    *       The whatever is added in result.add(ComputationCompiler.get_init();
+    *       needs to be re-evaluated at every iteration.
+    */
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/BinarySearch.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/BinarySearch.java
index 57580e7..b6e7a4b 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/BinarySearch.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/BinarySearch.java
@@ -170,10 +170,7 @@ public class BinarySearch
                new RelativeRef
                (
                   collection,
-                  Collections.singletonList
-                  (
-                     new Cast(value_of_result_index, Type.STRING)
-                  ),
+                  new Cast(value_of_result_index, Type.STRING),
                   element_type
                )
             )
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/Clear.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/Clear.java
index 17965ae..d63e8fb 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/Clear.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/Clear.java
@@ -82,10 +82,7 @@ public class Clear
             new RelativeRef
             (
                collection,
-               Collections.singletonList
-               (
-                  new Cast(value_of_iterator, Type.STRING)
-               ),
+               new Cast(value_of_iterator, Type.STRING),
                element_type
             )
          )
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
index dba37dc..5484e8a 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/InsertAt.java
@@ -92,10 +92,7 @@ public class InsertAt
             new RelativeRef
             (
                collection,
-               Collections.singletonList
-               (
-                  new Cast(value_of_end, Type.STRING)
-               ),
+               new Cast(value_of_end, Type.STRING),
                element_type
             ),
             new ValueOf
@@ -103,10 +100,7 @@ public class InsertAt
                new RelativeRef
                (
                   collection,
-                  Collections.singletonList
-                  (
-                     new Cast(value_of_prev, Type.STRING)
-                  ),
+                  new Cast(value_of_prev, Type.STRING),
                   element_type
                )
             )
@@ -142,10 +136,7 @@ public class InsertAt
             new RelativeRef
             (
                collection,
-               Collections.singletonList
-               (
-                  new Cast(value_of_index, Type.STRING)
-               ),
+               new Cast(value_of_index, Type.STRING),
                element_type
             ),
             element
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/InstructionManager.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/InstructionManager.java
index b3ea40f..74fe200 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/InstructionManager.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/InstructionManager.java
@@ -162,11 +162,15 @@ public class InstructionManager
 
    public Instruction merge (final List<Instruction> instructions)
    {
-      if (instructions.size() == 0)
+      if (instructions.isEmpty())
       {
          /* Important in case of label on InstructionList */
          return NOP.generate(this);
       }
+      else if (instructions.size() == 1)
+      {
+         return instructions.get(0);
+      }
 
       return new InstructionList(instructions);
    }
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/IterativeSearch.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/IterativeSearch.java
index 1d4c471..dabec5a 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/IterativeSearch.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/IterativeSearch.java
@@ -115,10 +115,7 @@ public class IterativeSearch
                      new RelativeRef
                      (
                         collection,
-                        Collections.singletonList
-                        (
-                           new Cast(value_of_result_index, Type.STRING)
-                        ),
+                        new Cast(value_of_result_index, Type.STRING),
                         target_type
                      )
                   ),
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAllOf.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAllOf.java
index cba50b5..bd9bb1e 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAllOf.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAllOf.java
@@ -104,10 +104,7 @@ public class RemoveAllOf
          new RelativeRef
          (
             collection,
-            Collections.singletonList
-            (
-               new Cast(value_of_index, Type.STRING)
-            ),
+            new Cast(value_of_index, Type.STRING),
             element_type
          );
 
@@ -162,13 +159,10 @@ public class RemoveAllOf
             new RelativeRef
             (
                collection,
-               Collections.singletonList
+               new Cast
                (
-                  new Cast
-                  (
-                     Operation.plus(value_of_index, value_of_found),
-                     Type.STRING
-                  )
+                  Operation.plus(value_of_index, value_of_found),
+                  Type.STRING
                ),
                element_type
             )
@@ -209,13 +203,10 @@ public class RemoveAllOf
             new RelativeRef
             (
                collection,
-               Collections.singletonList
+               new Cast
                (
-                  new Cast
-                  (
-                     Operation.plus(value_of_end, value_of_found),
-                     Type.STRING
-                  )
+                  Operation.plus(value_of_end, value_of_found),
+                  Type.STRING
                ),
                element_type
             )
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAt.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAt.java
index be5a859..050a8c6 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAt.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/RemoveAt.java
@@ -80,10 +80,7 @@ public class RemoveAt
          new RelativeRef
          (
             collection,
-            Collections.singletonList
-            (
-               new Cast(value_of_index, Type.STRING)
-            ),
+            new Cast(value_of_index, Type.STRING),
             element_type
          );
 
@@ -110,10 +107,7 @@ public class RemoveAt
                new RelativeRef
                (
                   collection,
-                  Collections.singletonList
-                  (
-                     new Cast(value_of_next, Type.STRING)
-                  ),
+                  new Cast(value_of_next, Type.STRING),
                   element_type
                )
             )
diff --git a/src/core/src/tonkadur/wyrd/v1/compiler/util/While.java b/src/core/src/tonkadur/wyrd/v1/compiler/util/While.java
index 1101a4c..c2e7d16 100644
--- a/src/core/src/tonkadur/wyrd/v1/compiler/util/While.java
+++ b/src/core/src/tonkadur/wyrd/v1/compiler/util/While.java
@@ -68,4 +68,60 @@ public class While
 
       return assembler.merge(result);
    }
+
+   /*
+    * Instruction cond_init
+    * Computation boolean condition
+    * Instruction while_body
+    *
+    * (mark start_label cond_init)
+    * (set .pc (ifelse condition (label if_true_label) (label end_label)))
+    * (mark if_true_label while_body)
+    * (mark_after end_label (set .pc (label start_label)))
+    */
+   public static Instruction generate
+   (
+      final AnonymousVariableManager anonymous_variables,
+      final InstructionManager assembler,
+      final Instruction cond_init,
+      final Computation condition,
+      final Instruction while_body
+   )
+   {
+      final String start_label, if_true_label, end_label;
+      final List<Instruction> result;
+
+      start_label = assembler.generate_label("<while#start_label>");
+      if_true_label = assembler.generate_label("<while#if_true_label>");
+      end_label = assembler.generate_label("<while#end_label>");
+
+      result = new ArrayList<Instruction>();
+
+      result.add(assembler.mark(start_label, cond_init));
+
+      result.add
+      (
+         new SetPC
+         (
+            new IfElseComputation
+            (
+               condition,
+               assembler.get_label_constant(if_true_label),
+               assembler.get_label_constant(end_label)
+            )
+         )
+      );
+
+      result.add(assembler.mark(if_true_label, while_body));
+      result.add
+      (
+         assembler.mark_after
+         (
+            new SetPC(assembler.get_label_constant(start_label)),
+            end_label
+         )
+      );
+
+      return assembler.merge(result);
+   }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/Variable.java b/src/core/src/tonkadur/wyrd/v1/lang/Variable.java
index fee6ca4..7117b89 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/Variable.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/Variable.java
@@ -37,11 +37,6 @@ public class Variable
 
    public Ref get_ref ()
    {
-      return
-         new Ref
-         (
-            Collections.singletonList(new Constant(Type.STRING, name)),
-            type
-         );
+      return new Ref(new Constant(Type.STRING, name), type);
    }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/computation/AddRichTextEffect.java b/src/core/src/tonkadur/wyrd/v1/lang/computation/AddRichTextEffect.java
index 318e418..74f967a 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/computation/AddRichTextEffect.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/computation/AddRichTextEffect.java
@@ -1,20 +1,18 @@
 package tonkadur.wyrd.v1.lang.computation;
 
 import java.util.List;
-import java.util.Map;
 
 import tonkadur.wyrd.v1.lang.type.Type;
 
 import tonkadur.wyrd.v1.lang.meta.Computation;
 
-public class AddRichTextEffect extends Computation
+public class AddRichTextEffect extends RichText
 {
    /***************************************************************************/
    /**** MEMBERS **************************************************************/
    /***************************************************************************/
    protected final String effect_name;
    protected final List<Computation> effect_parameters;
-   protected final List<Computation> content;
 
    /***************************************************************************/
    /**** PUBLIC ***************************************************************/
@@ -27,11 +25,10 @@ public class AddRichTextEffect extends Computation
       final List<Computation> content
    )
    {
-      super(Type.RICH_TEXT);
+      super(content);
 
       this.effect_name = effect_name;
       this.effect_parameters = effect_parameters;
-      this.content = content;
    }
 
    /**** Accessors ************************************************************/
@@ -44,9 +41,4 @@ public class AddRichTextEffect extends Computation
    {
       return effect_parameters;
    }
-
-   public List<Computation> get_content ()
-   {
-      return content;
-   }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/computation/Newline.java b/src/core/src/tonkadur/wyrd/v1/lang/computation/Newline.java
index aa561b0..bd3fbe5 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/computation/Newline.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/computation/Newline.java
@@ -1,10 +1,8 @@
 package tonkadur.wyrd.v1.lang.computation;
 
-import tonkadur.wyrd.v1.lang.type.Type;
+import java.util.ArrayList;
 
-import tonkadur.wyrd.v1.lang.meta.Computation;
-
-public class Newline extends Computation
+public class Newline extends RichText
 {
    /***************************************************************************/
    /**** MEMBERS **************************************************************/
@@ -16,6 +14,6 @@ public class Newline extends Computation
    /**** Constructors *********************************************************/
    public Newline ()
    {
-      super(Type.STRING);
+      super(new ArrayList());
    }
 }
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/computation/Ref.java b/src/core/src/tonkadur/wyrd/v1/lang/computation/Ref.java
index 69aa905..006a2ea 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/computation/Ref.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/computation/Ref.java
@@ -1,7 +1,5 @@
 package tonkadur.wyrd.v1.lang.computation;
 
-import java.util.List;
-
 import tonkadur.wyrd.v1.lang.type.Type;
 
 import tonkadur.wyrd.v1.lang.meta.Computation;
@@ -11,25 +9,25 @@ public class Ref extends Computation
    /***************************************************************************/
    /**** MEMBERS **************************************************************/
    /***************************************************************************/
-   protected final List<Computation> accesses;
+   protected final Computation address;
    protected final Type target_type;
 
    /***************************************************************************/
    /**** PUBLIC ***************************************************************/
    /***************************************************************************/
    /**** Constructors *********************************************************/
-   public Ref (final List<Computation> accesses, final Type target_type)
+   public Ref (final Computation address, final Type target_type)
    {
       super(Type.POINTER);
 
-      this.accesses = accesses;
+      this.address = address;
       this.target_type = target_type;
    }
 
    /**** Accessors ************************************************************/
-   public List<Computation> get_accesses ()
+   public Computation get_address ()
    {
-      return accesses;
+      return address;
    }
 
    public Type get_target_type ()
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/computation/RelativeRef.java b/src/core/src/tonkadur/wyrd/v1/lang/computation/RelativeRef.java
index bc39075..2ab63cc 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/computation/RelativeRef.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/computation/RelativeRef.java
@@ -1,7 +1,5 @@
 package tonkadur.wyrd.v1.lang.computation;
 
-import java.util.List;
-
 import tonkadur.wyrd.v1.lang.type.Type;
 
 import tonkadur.wyrd.v1.lang.meta.Computation;
@@ -20,11 +18,11 @@ public class RelativeRef extends Ref
    public RelativeRef
    (
       final Ref parent,
-      final List<Computation> accesses,
+      final Computation member,
       final Type target_type
    )
    {
-      super(accesses, target_type);
+      super(member, target_type);
 
       this.parent = parent;
    }
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/computation/RichText.java b/src/core/src/tonkadur/wyrd/v1/lang/computation/RichText.java
new file mode 100644
index 0000000..a82b7ab
--- /dev/null
+++ b/src/core/src/tonkadur/wyrd/v1/lang/computation/RichText.java
@@ -0,0 +1,32 @@
+package tonkadur.wyrd.v1.lang.computation;
+
+import java.util.List;
+
+import tonkadur.wyrd.v1.lang.type.Type;
+
+import tonkadur.wyrd.v1.lang.meta.Computation;
+
+public class RichText extends Computation
+{
+   /***************************************************************************/
+   /**** MEMBERS **************************************************************/
+   /***************************************************************************/
+   protected final List<Computation> content;
+
+   /***************************************************************************/
+   /**** PUBLIC ***************************************************************/
+   /***************************************************************************/
+   /**** Constructors *********************************************************/
+   public RichText (final List<Computation> content)
+   {
+      super(Type.RICH_TEXT);
+
+      this.content = content;
+   }
+
+   /**** Accessors ************************************************************/
+   public List<Computation> get_content ()
+   {
+      return content;
+   }
+}
diff --git a/src/core/src/tonkadur/wyrd/v1/lang/instruction/Display.java b/src/core/src/tonkadur/wyrd/v1/lang/instruction/Display.java
index 3cae965..0256416 100644
--- a/src/core/src/tonkadur/wyrd/v1/lang/instruction/Display.java
+++ b/src/core/src/tonkadur/wyrd/v1/lang/instruction/Display.java
@@ -1,7 +1,5 @@
 package tonkadur.wyrd.v1.lang.instruction;
 
-import java.util.List;
-
 import tonkadur.wyrd.v1.lang.meta.Computation;
 import tonkadur.wyrd.v1.lang.meta.Instruction;
 
@@ -10,19 +8,19 @@ public class Display extends Instruction
    /***************************************************************************/
    /**** MEMBERS **************************************************************/
    /***************************************************************************/
-   protected final List<Computation> content;
+   protected final Computation content;
 
    /***************************************************************************/
    /**** PUBLIC ***************************************************************/
    /***************************************************************************/
    /**** Constructors *********************************************************/
-   public Display (final List<Computation> content)
+   public Display (final Computation content)
    {
       this.content = content;
    }
 
    /**** Accessors ************************************************************/
-   public List<Computation> get_content ()
+   public Computation get_content ()
    {
       return content;
    }