Add basic EOF handling to REPL

lib/include/repl.h

@@ -6,12 +6,6 @@
 #define REPL_LINE_BUFFER_SIZE 128
 #define REPL_RESULT_BUFFER_SIZE 128
 
-typedef enum {
-	REPL_OK,
-	REPL_ERROR,
-	REPL_EXIT,
-} repl_status_t;
-
 typedef int (*get_byte_fn_t)(void);
 typedef const expression_t *(*read_fn_t)(
     memory_pool_t *pool, const char *input, int len);
@@ -29,7 +23,7 @@ typedef struct {
 } repl_t;
 
 void init_repl(repl_t *repl);
-void step_repl(repl_t *repl);
+bool step_repl(repl_t *repl);
 void run_repl(repl_t *repl);
 
 #endif