REPL: checks if EOF

Check if newline to not create empty println

compiler/main.v

@@ -1313,9 +1313,12 @@ fn run_repl() []string {
 			continue
 		}
 		line = line.trim_space()
-		if line == '' || line == 'exit' {
+		if line.len == -1 || line == '' || line == 'exit' {
 			break
 		}
+		if line == '\n' {
+			continue
+		}
 		// Save the source only if the user is printing something,
 		// but don't add this print call to the `lines` array,
 		// so that it doesn't get called during the next print.