diff --git a/src/ast.c b/src/ast.c
index e8d0b17..7a0023a 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -2,6 +2,7 @@
 
 #include "include/ast.h"
 #include "include/util.h"
+#include "include/dstr.h"
 
 extern AST* root;
 
@@ -30,14 +31,29 @@ void ast_destroy(AST* ast) {
 }
 
 void ast_print(AST* ast) {
-    log_dbgf("Tree type: %s", asttype_names[ast->type]);
-    fflush(stdout);
+    ast_print_i(ast, 0);
 }
 
+void ast_print_i(AST* ast, int i) {
+    INDENT_BEGIN(i);
+
+    INDENT_TITLE("AST", ast);
+    INDENT_FIELD("type", "%s", asttype_names[ast->type]);
+    INDENT_FIELD_EXT_NONL_START("data");
+    switch (ast->type) {
+        case AST_TYPE_NUM: ast_num_print(ast->data, i + 1); break;
+        case AST_TYPE_CALL: ast_call_print(ast->data, i + 1); break;
+        default: exit(1);
+    }
+    INDENT_FIELD_NONL_END;
+    INDENT_END;
+}
 
 ASTNumData* ast_num_data_init(double val) {
     talloc(ASTNumData, num);
 
+    log_dbgf("val: %lf", val);
+
     *num = val;
 
     return num;
@@ -47,9 +63,19 @@ void ast_num_data_destroy(ASTNumData* num) {
     if (!num) return free(num);
 }
 
+void ast_num_print(ASTNumData* data, int i) {
+    INDENT_BEGIN(i);
+
+    INDENT_FIELD("data", "%lf", *data);
+
+    INDENT_END;
+}
+
 ASTCallData* ast_call_data_init(char* to, size_t argc, AST** argv) {
     talloc(ASTCallData, call);
 
+    log_dbgf("to: %s", to);
+
     call->to = to;
     call->argc = argc;
     call->argv = argv;
@@ -62,3 +88,14 @@ void ast_call_data_destroy(ASTCallData* call) {
     for (size_t i = 0; i < call->argc; i++) free(call->argv[i]);
     free(call);
 }
+
+void ast_call_print(ASTCallData* data, int i) {
+    INDENT_BEGIN(i);
+
+    INDENT_TITLE("ASTCallData", data);
+    INDENT_FIELD("to", "%s", data->to);
+    INDENT_FIELD("argc", "%ld", data->argc);
+    INDENT_FIELD_LIST("argv", data->argv, data->argc, ast_print_i);
+
+    INDENT_END;
+}
diff --git a/src/exec.c b/src/exec.c
index 0ade84a..fc34b6f 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -7,26 +7,35 @@
 
 extern AST* root;
 
-void exec_expr() {
-    ast_print(root);
+ASTNumData exec_expr(AST* ast) {
+    ast_print(ast);
     log_dbg("Started execution.");
-    switch (root->type) {
-    case AST_TYPE_CALL: exec_call(); break;
-    default:            printf("what\n");
+    switch (ast->type) {
+    case AST_TYPE_CALL: return exec_call(ast);
+    case AST_TYPE_NUM:
+        exec_print(*(ASTNumData*)ast->data);
+        return *(ASTNumData*)ast->data;
+    default: printf("what\n");
     }
 }
 
-void exec_call() {
+ASTNumData exec_call(AST* ast) {
     log_dbg("Started call execution.");
     fflush(stdout);
-    ASTCallData* calldata = (ASTCallData*)root->data;
+    ASTCallData* calldata = (ASTCallData*)ast->data;
     if (!strcmp(calldata->to, "+") && calldata->argc == 2) {
 
+        /*
         ASTNumData* n1 = (ASTNumData*)calldata->argv[0]->data;
         ASTNumData* n2 = (ASTNumData*)calldata->argv[1]->data;
+        */
 
-        exec_return(*n1 + *n2);
+        ASTNumData n1 = exec_expr(calldata->argv[0]);
+        ASTNumData n2 = exec_expr(calldata->argv[1]);
+
+        return n1 + n2;
     }
+    return -1000;
 }
 
-void exec_return(double n) { printf("= %lf\n", n); }
+void exec_print(double n) { printf("= %lf\n", n); }
diff --git a/src/grammar.y b/src/grammar.y
index 67e30c7..e194cf9 100644
--- a/src/grammar.y
+++ b/src/grammar.y
@@ -36,12 +36,16 @@ input:
 
 exp:
     NUM { $$ = ast_init(AST_TYPE_NUM, ast_num_data_init($1)); }
-    | NUM PLUS NUM {
+    | NUM PLUS exp {
         AST* argv[2] = {
             ast_init(AST_TYPE_NUM, ast_num_data_init($1)),
-            ast_init(AST_TYPE_NUM, ast_num_data_init($3))
+            $3
         };
         $$ = ast_init(AST_TYPE_CALL, ast_call_data_init("+", 2, argv));
-    };
+    }/*
+    | exp PLUS exp {
+        AST* argv[2] = { $1, $3 };
+        $$ = ast_init(AST_TYPE_CALL, ast_call_data_init("+", 2, argv));
+    };*/
 
 %%
diff --git a/src/include/ast.h b/src/include/ast.h
index e6ca0f1..c13d760 100644
--- a/src/include/ast.h
+++ b/src/include/ast.h
@@ -17,11 +17,13 @@ typedef struct {
 AST* ast_init(ASTType type, void* data);
 void ast_destroy(AST* ast);
 void ast_print(AST* ast);
+void ast_print_i(AST* ast, int i);
 
 typedef double ASTNumData;
 
 ASTNumData* ast_num_data_init(double val);
 void ast_num_data_destroy(ASTNumData* num);
+void ast_num_print(ASTNumData*, int i);
 
 typedef struct {
     char* to;       // What the call's to.
@@ -31,5 +33,6 @@ typedef struct {
 
 ASTCallData* ast_call_data_init(char* to, size_t argc, AST** argv);
 void ast_call_data_destroy(ASTCallData* call);
+void ast_call_print(ASTCallData*, int i);
 
 #endif
diff --git a/src/include/exec.h b/src/include/exec.h
index c8a4389..7848443 100644
--- a/src/include/exec.h
+++ b/src/include/exec.h
@@ -1,8 +1,10 @@
 #ifndef EXEC_H
 #define EXEC_H
 
-void exec_expr();
-void exec_call();
-void exec_return(double n);
+#include "ast.h"
+
+ASTNumData exec_expr(AST* ast);
+ASTNumData exec_call(AST* ast);
+void exec_print(double n);
 
 #endif
diff --git a/src/include/util.h b/src/include/util.h
index dccc37b..ed54c58 100644
--- a/src/include/util.h
+++ b/src/include/util.h
@@ -64,8 +64,8 @@
            INDENT_spacing->buf, INDENT_spacing->buf, __VA_ARGS__);
 
 // Print & indent a thing without any newline.
-#define INDENT_FIELD_NONL_START(FIELD)                                         \
-    printf("%s " COL_BWHI FIELD ": " COL_RESET COL_WHI, INDENT_spacing->buf);
+#define INDENT_FIELD_EXT_NONL_START(FIELD)                                         \
+    printf("%s " COL_BWHI FIELD ":\n" COL_RESET COL_WHI, INDENT_spacing->buf);
 #define INDENT_FIELD_NONL_END printf( "\n" COL_RESET);
 
 // Print an array A of N things, by calling the function F.
diff --git a/src/lexer.c b/src/lexer.c
index 74dd64f..8b579d1 100644
--- a/src/lexer.c
+++ b/src/lexer.c
@@ -15,6 +15,7 @@ int acc_int(int c) {
 }
 
 double acc_float(int c) {
+    int dplaces = 0;
     double value = (double)(c - '0');
 
     // Grab everything prior to '.'.
@@ -24,13 +25,17 @@ double acc_float(int c) {
     }
 
     if (*inp ==  '.') {
-        char* oinp = inp++;
+        inp++;
+
         while (isdigit(*inp)) {
             // TODO:
             // Accumulate as int, divide once at end.
-            value = value + (((double)(*inp - '0'))/pow(10.0l, (double)(inp-oinp))); // Accumulate value.
+            // value = value + (((double)(*inp - '0'))/pow(10.0l, (double)(inp-oinp))); // Accumulate value.
+            value = value * 10 + (*inp - '0'); // Accumulate value.
+            dplaces++;
             inp++;
         }
+        value = value / pow(10, dplaces);
     }
 
     // > 1.20000
@@ -66,4 +71,4 @@ int yylex() {
 
     return 0;
 }
-void yyerror(char const* s) { fprintf(stderr, "Syntax error:\n%s\n", s); }
+void yyerror(char const* s) { fprintf(stderr, "Parse error: %s\n", s); }
diff --git a/src/main.c b/src/main.c
index cc73cdf..ecb0327 100644
--- a/src/main.c
+++ b/src/main.c
@@ -48,7 +48,8 @@ int main(int argc, char** argv) {
             else
                 printf("Parse error.\n");
 
-            exec_expr();
+            //exec_expr(root);
+            ast_print(root);
         }
 
         dstr_destroy(ln);