fix return 0 show error_box

tools/smart_write

@@ -0,0 +1,19 @@
+#!/usr/bin/env miaou-bash
+
+function usage {
+  builtin echo "Usage: $(basename "$0") <REGEX> <STRING> <FILE>"
+}
+
+[[ $# -ne 3 ]] && usage && exit 2
+
+REGEX=$1
+STRING=$2
+FILE=$3
+
+if ! grep -Pq "$REGEX" "$FILE"; then
+  builtin echo -e "$STRING" >>"$FILE"
+  echo 'appended'
+else
+  sed -Ei "s|$REGEX|$STRING|g" "$FILE"
+  echo 'replaced'
+fi