From 34fe4da417ccd53320105a314f7eaf43104cfef8 Mon Sep 17 00:00:00 2001
From: Paul Campbell <pcampbell@kemitix.net>
Date: Sun, 30 Jul 2023 15:08:26 +0100
Subject: [PATCH] box up FileEnv's functions

---
 src/file/env.rs | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/file/env.rs b/src/file/env.rs
index 005ced2..5635b67 100644
--- a/src/file/env.rs
+++ b/src/file/env.rs
@@ -1,15 +1,19 @@
 use std::fs::{File, OpenOptions};
 use std::io::Write;
 
+pub type FileOpenFn = Box<dyn Fn(&str) -> std::io::Result<File>>;
+
+pub type FileAppendLineFn = Box<dyn Fn(&str, &str) -> std::io::Result<()>>;
+
 pub struct FileEnv {
-    pub open: FileOpen,
-    pub append_line: FileAppendLine,
+    pub open: FileOpenFn,
+    pub append_line: FileAppendLineFn,
 }
 impl Default for FileEnv {
     fn default() -> Self {
         Self {
-            open: |path| File::open(path),
-            append_line: |file_name, line| {
+            open: Box::new(|path| File::open(path)),
+            append_line: Box::new(|file_name, line| {
                 let mut file = OpenOptions::new()
                     .write(true)
                     .append(true)
@@ -18,9 +22,7 @@ impl Default for FileEnv {
                     .unwrap();
                 writeln!(file, "{}", line)?;
                 Ok(())
-            },
+            }),
         }
     }
 }
-pub type FileOpen = fn(path: &str) -> std::io::Result<File>;
-pub type FileAppendLine = fn(paht: &str, line: &str) -> std::io::Result<()>;