Add with_config{_mut}

src/utils/mod.rs

@@ -19,6 +19,8 @@ use std::io::Read;
 use std::path::Path;
 use internal::prelude::*;
 use model::{EmojiId, EmojiIdentifier};
+use cache::Cache;
+use ::CACHE;
 
 /// Determines if a name is NSFW.
 ///
@@ -432,3 +434,41 @@ pub fn parse_quotes(s: &str) -> Vec<String> {
 /// ```
 #[inline]
 pub fn shard_id(guild_id: u64, shard_count: u64) -> u64 { (guild_id >> 22) % shard_count }
+
+/// A function for doing automatic `read`ing (and the releasing of the guard as well)
+/// This is particularly useful if you just want to use the cache for this one time,
+/// or don't want to be messing with the `RwLock` directly.
+///
+/// # Examples
+///
+/// Return the bot's id
+///
+/// ```rust,ignore
+/// use serenity::utils;
+/// 
+/// // assuming that the id is `1234`:
+/// assert_eq!(1234, utils::with_cache(|cache| cache.user.id));
+/// ```
+pub fn with_cache<T, F>(f: F) -> T where F: Fn(&Cache) -> T {
+    let cache = CACHE.read().unwrap();
+    f(&cache)
+}
+
+/// Like [`with_cache`] but as the name says, allows for modifications to be done.
+///
+/// # Examples
+///
+/// Return the bot's id, and changes the shard count
+///
+/// ```rust,ignore
+/// use serenity::utils;
+/// 
+/// // assuming that the id is `1234`:
+/// assert_eq!(1234, utils::with_cache_mut(|cache| { cache.shard_count = 8; cache.user.id }));
+/// ```
+///
+/// [`with_cache`]: #fn.with_cache
+pub fn with_cache_mut<T, F>(mut f: F) -> T where F: FnMut(&mut Cache) -> T {
+    let mut cache = CACHE.write().unwrap();
+    f(&mut cache)
+}