From 1e4bdde8e36b29b411b6a113f586d040abac331f Mon Sep 17 00:00:00 2001
From: Frank Duncan <frank@kank.net>
Date: Mon, 25 Apr 2016 23:52:19 -0500
Subject: [PATCH] Prims - Implement let

---
 src/main/code-parse.lisp  |  2 +-
 src/main/transpile.lisp   | 36 +++++++++++++++++++++++++++++++++---
 src/test/simpletests.lisp |  6 ++++++
 3 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/src/main/code-parse.lisp b/src/main/code-parse.lisp
index c0e553b..7d9c42c 100644
--- a/src/main/code-parse.lisp
+++ b/src/main/code-parse.lisp
@@ -119,5 +119,5 @@ DESCRIPTION:
 
   Returns the globals that get declared in the code."
  (mapcar
-  (lambda (global) (list (symbol-name global) 0d0))
+  (lambda (global) (list (intern (symbol-name global) clnl:*model-package*) 0d0))
   (cdr (second (find :globals code-parsed-ast :key #'car)))))
diff --git a/src/main/transpile.lisp b/src/main/transpile.lisp
index a45183b..690fa3e 100644
--- a/src/main/transpile.lisp
+++ b/src/main/transpile.lisp
@@ -3,6 +3,8 @@
 (defparameter *prims* nil)
 (defparameter *prim-aliases* nil)
 
+(defvar *local-variables* nil)
+
 (defun prim-name (prim) (getf prim :name))
 (defun prim-type (prim) (getf prim :type))
 (defun prim-func (prim) (getf prim :func))
@@ -34,7 +36,32 @@ DESCRIPTION:
   running engine.  This is the entry point for commands, so it does
   extra checking to ensure that commands are actually in the PARSED-AST."
  `(progn
-   ,@(mapcar #'transpile-command parsed-ast)))
+   ,@(transpile-commands-inner parsed-ast)))
+
+(defun transpile-commands-inner (parsed-ast)
+ (cond
+  ((not parsed-ast) nil)
+  ((and (listp (car parsed-ast)) (eql :let (caar parsed-ast))) (list (handle-let parsed-ast)))
+  (t
+   (cons
+    (transpile-command (car parsed-ast))
+    (transpile-commands-inner (cdr parsed-ast))))))
+
+(defun handle-let (parsed-ast &optional vars)
+ (if
+  (and (listp (car parsed-ast)) (eql :let (caar parsed-ast)))
+  (let
+   ((*local-variables* (cons (second (car parsed-ast)) *local-variables*)))
+   (handle-let
+    (cdr parsed-ast)
+    (cons
+     (list
+      (transpile-reporter (second (car parsed-ast)))
+      (transpile-reporter (third (car parsed-ast))))
+     vars)))
+  `(let*
+    ,vars
+    ,@(transpile-commands-inner parsed-ast))))
 
 (defun transpile-command (command)
  (cond
@@ -63,15 +90,18 @@ DESCRIPTION:
   The Common lisp code that is returned, when run, will return some value."
  (cond
   ((numberp reporter) reporter) ; The parser converts to double for us
-  ((symbolp reporter) reporter) ; The parser should have checked that having a symbol here is ok
+  ; The parser should have checked that having a symbol here is ok
+  ((symbolp reporter) (intern (symbol-name reporter) clnl:*model-package*))
   ((not (listp reporter)) (error "Expected a statement of some sort"))
   ((eql :command-block (car reporter)) (transpile-command-block reporter))
+  ((and (symbolp (car reporter)) (find (car reporter) *local-variables*))
+   (intern (symbol-name (car reporter)) clnl:*model-package*))
   ((not (find-prim (car reporter))) (error "Couldn't find the reporter for ~S" (car reporter)))
   ((not (is-reporter (find-prim (car reporter)))) (error "Expected reporter, got ~S" (car reporter)))
   (t (apply (prim-func (find-prim (car reporter))) (mapcar #'transpile-reporter (cdr reporter))))))
 
 (defun transpile-command-block (block)
- `(lambda () ,@(mapcar #'transpile-command (cdr block))))
+ `(lambda () ,@(transpile-commands-inner (cdr block))))
 
 ; Undoes the previous function :)
 (defun make-command-block-inline (block)
diff --git a/src/test/simpletests.lisp b/src/test/simpletests.lisp
index c2a11ba..6a3e53f 100644
--- a/src/test/simpletests.lisp
+++ b/src/test/simpletests.lisp
@@ -137,3 +137,9 @@
 
 (defsimplereportertest "colors 2" "black" "0"
  "E1DE30F072D785E0D0B59F28B0F7853E3D3E0D8B")
+
+(defsimplecommandtest "let 1" "let a 5 crt a"
+ "9FE588C2749CD9CE66CB0EA451EFB80476E881FB")
+
+(defsimplecommandtest "let 2" "let a 5 let b 6 crt (a + b)"
+ "4ABB6822402929878AB9E5A1084B9E4AE1F01D5B")
-- 
2.25.1