Update README.md

Author: zserge

README.md

@@ -22,31 +22,31 @@ input and returns floating-point number as a result.
 #include "expr.h"
 
 // Custom function that returns the sum of its two arguments
-static float add(struct expr_func *f, vec_expr_t args, void *c) {
-  float a = expr_eval(&vec_nth(&args, 0));
-  float b = expr_eval(&vec_nth(&args, 1));
+static float add(struct expr_func *f, vec_expr_t *args, void *c) {
+  float a = expr_eval(&vec_nth(args, 0));
+  float b = expr_eval(&vec_nth(args, 1));
   return a + b;
 }
 
-static struct expr_func funcs[] = {
-	{"add", add, 0},
-	{NULL, NULL, 0},
+static struct expr_func user_funcs[] = {
+    {"add", add, NULL, 0},
+    {NULL, NULL, NULL, 0},
 };
 
 int main() {
-	const char *s = "x = 5, add(2, x)";
+  const char *s = "x = 5, add(2, x)";
   struct expr_var_list vars = {0};
   struct expr *e = expr_create(s, strlen(s), &vars, user_funcs);
   if (e == NULL) {
     printf("Syntax error");
-		return 1;
-	}
+    return 1;
+  }
 
-	float result = expr_eval(e);
-	printf("result: %f\n", result);
+  float result = expr_eval(e);
+  printf("result: %f\n", result);
 
-	expr_destroy(e, &vars);
-	return 0;
+  expr_destroy(e, &vars);
+  return 0;
 }
 ```