lexer: add number parsing

2 files changed, 50 insertions, 2 deletions

diff --git a/include/lexer.h b/include/lexer.h
index d6936f3..8122848 100644
--- a/include/lexer.h
+++ b/include/lexer.h
@@ -21,10 +21,12 @@ private:
   bool at_end(void);
   char advance(void);
   char peek(void);
+  char peek_next(void);
   bool match(char c);
 
 private:
   void string(void);
+  void number(void);
 
 private:
   void add_token(token_type_e type);
diff --git a/src/lexer.cc b/src/lexer.cc
index c77e11d..33e364f 100644
--- a/src/lexer.cc
+++ b/src/lexer.cc
@@ -1,3 +1,4 @@
+#include <ctype.h>
 #include <lexer.h>
 #include <list.h>
 #include <stdio.h>
@@ -70,6 +71,15 @@ Lexer::peek(void)
   return m_script[m_current];
 }
 
+char
+Lexer::peek_next(void)
+{
+  if (m_current + 1 >= m_end)
+    return '\0';
+
+  return m_script[m_current + 1];
+}
+
 bool
 Lexer::match(char c)
 {
@@ -103,6 +113,7 @@ Lexer::string(void)
 
   char *lexeme;
   asprintf(&lexeme, "%.*s", token_length, m_script + m_start + 1);
+
   Token token;
   token.init(STRING, lexeme, m_line);
   m_tokens->add(&token);
@@ -112,6 +123,35 @@ Lexer::string(void)
 }
 
 void
+Lexer::number(void)
+{
+  while (isdigit(peek())) {
+    printf("%c\n", peek());
+    advance();
+  }
+
+  if (peek() == '.' && isdigit(peek_next())) {
+    // .
+    advance();
+
+    while (isdigit(peek()))
+      advance();
+  }
+
+  int token_length = m_current - m_start;
+  if (token_length == 0)
+    token_length++;
+
+  char *lexeme;
+  asprintf(&lexeme, "%.*s", token_length, m_script + m_start);
+
+  Token token;
+  token.init(NUMBER, lexeme, m_line);
+  m_tokens->add(&token);
+  token.clean();
+}
+
+void
 Lexer::add_token(token_type_e type)
 {
   int token_length = m_current - m_start;
@@ -198,8 +238,14 @@ Lexer::scan_token(void)
     break;
 
   default:
-    printf("[-] Error: Unexpected character %c in line %lu\n", c, m_line);
-    m_errored = true;
+    if (isdigit(c))
+      number();
+
+    else {
+      printf("[-] Error: Unexpected character %c in line %lu\n", c, m_line);
+      m_errored = true;
+    }
+
     break;
   }
 }