From b1183af95f45ba0162a91f7a308a4846418f03be Mon Sep 17 00:00:00 2001
From: Ben Winston
Date: Sun, 21 May 2023 13:57:41 -0400
Subject: move to using 2 stacks

---
 parser.d | 24 +++++++++++++++++++++---
 1 file changed, 21 insertions(+), 3 deletions(-)

(limited to 'parser.d')

diff --git a/parser.d b/parser.d
index 978b218..80e1626 100644
--- a/parser.d
+++ b/parser.d
@@ -252,6 +252,7 @@ class Parser {
     int line;
 
     bool peekable() {
+        writefln("pos %d source %d", pos, source.length);
         return (pos < source.length);
     }
 
@@ -259,25 +260,36 @@ class Parser {
         if (pos < source.length) {
             return source[pos];
         } else {
-            //writeln("peek returns null");
+            writeln("peek returns null");
             return '\0';
         }
     }
 
     char advance() {
+        if (!peekable()) {
+            writeln("trying to advance() beyond the end!!!");
+            return '\0';
+        } else {
+            char ret = peek();
+            pos++;
+            return ret;
+        }
+        /*
         char ret = peek();
         if (ret != '\0') {
             pos++;
         }
         return ret;
+        */
     }
 
     void skipWhitespace() {
-        while (canFind([' ', '\t', '\r', '\n'], peek())) {
+        while (peekable() && canFind([' ', '\t', '\r', '\n'], peek())) {
             if (peek() == '\n') {
                 line++;
             }
-            pos++;
+            //pos++;
+            advance();
         }
     }
 
@@ -353,6 +365,8 @@ class Parser {
 
         advance();  // closing paren
 
+        writefln("ending DEF pos %d", pos);
+
         return def;
     }
 
@@ -406,6 +420,7 @@ class Parser {
             return new ParseError("unterminated block", line);
         }
 
+        writefln("ending block pos %d", pos);
         advance();  // consume closing paren
 
         return block;
@@ -480,6 +495,9 @@ class Parser {
             default:
                 return parseSymbol();
         }
+
+        writeln("FELL THROUGH ON PARSE FORM");
+
         advance();
 
         return new Atom(0, -1);
-- 
cgit v1.2.3