Move REPL logic into application

app/main.c

@@ -1,12 +1,36 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#include "repl.h"
+#include "evaluator.h"
+#include "reader.h"
 
-static repl_t repl;
+#define BUFFER_SIZE 128U
+
+static memory_pool_t pool;
+static char buffer[BUFFER_SIZE];
+
+static bool step_repl(void)
+{
+	init_memory_pool(&pool);
+
+	const int len = read_line(getchar, buffer, BUFFER_SIZE);
+	if (len < 0)
+		return false;
+	const expression_t *e = read_expression(&pool, buffer, len);
+	if (NULL == e) {
+		puts("Invalid expression\n");
+		return true;
+	}
+
+	const int result = evaluate(e);
+	printf("%d\n", result);
+
+	return true;
+}
 
 int main(void)
 {
-	run_repl(&repl);
+	while (step_repl())
+		;
 	return EXIT_SUCCESS;
 }