README: add DMA counter syntax note

README.rst

@@ -56,6 +56,11 @@ example as invalid: it misleads what the result of the operation is.
 This change is consistent with what is written in the SCU manual
 (ST-97-R5-072694), but is inconsistent with SEGA's SCU DSP examples.
 
+.. note::
+
+   It is currently unclear which of the two is correct. A future
+   version of scu-dsp-asm may change this behavior.
+
 Differences that affect code generation
 =======================================
 
@@ -85,8 +90,8 @@ In short:
 Spurious invalid X-bus opcode generation
 ----------------------------------------
 
-Under seemly-random circumstances, ``dspasm.exe`` emits the undefined
+Under seemingly-random circumstances, ``dspasm.exe`` emits the
-X-bus opcode ``001``. Given:
+undefined X-bus opcode ``001``. Given:
 
 .. code::
    

lexer_iterator.cpp

@@ -1,35 +0,0 @@
-#include "lexer.hpp"
-#include "token.hpp"
-
-namespace dsp {
-
-struct lexer_iterator_t
-{
-  token_t previous_token;
-  token_t current_token;
-  lexer_t& lexer;
-
-  lexer_iterator_t(lexer_t& lexer)
-    : lexer(lexer), previous_token(lexer.scan_token()), current_token(previous_token)
-  {
-  }
-
-  token_t& advance()
-  {
-    previous_token = current_token;
-    current_token = lexer.scan_token();
-    return previous_token;
-  }
-
-  token_t& peek()
-  {
-    return current_token;
-  }
-
-  token_t& previous()
-  {
-    return previous_token;
-  }
-};
-
-}