From 1517d38d21ae49af3dc63d5891e07255f79afa30 Mon Sep 17 00:00:00 2001
From: Denis Tereshkin <denis@kasan.ws>
Date: Sun, 19 Dec 2021 11:22:16 +0700
Subject: [PATCH] Bugfix: vmcompiler: parse numeric offset in static segment

Apparently, numeric arguments to push/pop static are valid,
so I prefix them with 'STATIC_' at the parsing stage
---
 src/Nand2Tetris/VM.hs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/Nand2Tetris/VM.hs b/src/Nand2Tetris/VM.hs
index 33fa744..06b24ed 100644
--- a/src/Nand2Tetris/VM.hs
+++ b/src/Nand2Tetris/VM.hs
@@ -129,7 +129,7 @@ parseInstruction =
                parseSegmentInt "this"  SThis,
                parseSegmentInt "that"  SThat,
                parseSegmentInt "constant" SConstant,
-               (string "static" *> space1) *> (SStatic <$> parseId),
+               (string "static" *> space1) *> (SStatic <$> (try parseId <|> parseStaticOffset)),
                parseSegmentInt "pointer" SPointer,
                parseSegmentInt "temp" STemp
              ]
@@ -141,6 +141,10 @@ parseInstruction =
       hs <- many (alphaNumChar <|> char '.' <|> char '_')
       return $ T.pack (h : hs)
 
+    parseStaticOffset :: Parser T.Text
+    parseStaticOffset = do
+      h <- L.decimal
+      return $ "STATIC_" <> (T.pack . show) h
 
     parseSegmentInt :: T.Text -> (Int -> Segment) -> Parser Segment
     parseSegmentInt sname f = try $ do