parsin like mofo

alandipert · Jul 2, 2009 · 0d4c23e · 0d4c23e
1 parent 09c04bf
commit 0d4c23e
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Showing 2 changed files with 55 additions and 8 deletions.
diff --git a/.Makefile.swp b/.Makefile.swp
diff --git a/parse.c b/parse.c
@@ -20,26 +20,50 @@ static Token* t_append(Token *t1, Token *t2) {
   }
 }
 
+//recursively free child tokens
+static void t_free(Token *t) {
+}
+
 static Token* t_rewind(Token *t) {
   while(t->prev) {
     t = t->prev;
   }
   return t;
 }
 
-static void t_pp(Token *t) {
+static void t_tab(int level) {
+  while(level--) {
+    printf("\t");
+  }
+}
+
+static char* op_pp(enum operator_type op) {
+  switch(op) {
+    case ADD: return "add";
+    case SUBTRACT: return "subtract";
+    case MULTIPLY: return "multiply";
+    case DIVIDE: return "divide";
+    default: return "unknown";
+  }
+}
+
+static void t_pp(Token *t, int level) {
   if(t != NULL) {
     t = t_rewind(t);
     do {
       switch(t->type) {
         case ATOM:
-          printf("val: %f\n", t->n_value);
+          t_tab(level);
+          printf("atom: %f\n", t->n_value);
           break;
         case OPERATOR:
-          printf("operator\n");
+          t_tab(level);
+          printf("%s\n", op_pp(t->o_type));
           break;
         case LIST:
+          t_tab(level);
           printf("list\n");
+          t_pp(t->head, level+1);
           break;
       }
     } while ((t = t->next));
@@ -53,8 +77,32 @@ static Token* tokenize(char *input) {
   Token *last_token = NULL;
   char buf[100];
   for(i = 0; i < strlen(input); i++) {
-    //numbers
+    if(input[i] == '(') {
-    if(isdigit(input[i])) {
+      int p_count = 1;
+      char tmp;
+      m_start = &input[i+1];
+      m_count = 0;
+      while((tmp = input[i+(++m_count)]) != '\0' && p_count != 0) {
+        if(tmp == '(') {
+          p_count++;
+        } else if(tmp == ')') {
+          p_count--;
+        }
+      }
+      if(p_count) {
+        fprintf(stderr, "unmatched parens\n");
+        exit(1);
+      } else {
+        /*printf("all parens match\n");*/
+        strncpy(buf, m_start, m_count-1);
+        buf[m_count-2] = '\0';
+        Token *t2 = t_mk();
+        t2->type = LIST;
+        t2->head = tokenize(buf);
+        last_token = t_append(last_token, t2);
+      }
+      i += m_count;
+    } else if(isdigit(input[i])) {
       m_start = &input[i];
       m_count = 1;
       while(isdigit(m_start[m_count]) || m_start[m_count] == '.'){
@@ -64,7 +112,7 @@ static Token* tokenize(char *input) {
       t2->type = ATOM;
       t2->a_type = NUMBER;
       strncpy(buf, m_start, m_count);
-      buf[m_count+1] = '\0';
+      buf[m_count] = '\0';
       t2->n_value = atof(buf);
       last_token = t_append(last_token, t2);
       i += m_count;
@@ -77,10 +125,9 @@ static Token* tokenize(char *input) {
     }
   }
 
-  t_pp(last_token);
   return last_token;
 }
 
 void eval(char *input) {
-  tokenize(input);
+  t_pp(tokenize(input), 0);
 }