add collect_fragment_async() helper method

rscx/Cargo.toml

@@ -11,7 +11,9 @@ readme = "../README.md"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+async-trait = "0.1.73"
 axum = { version = "0.6.20", features = ["macros"], optional = true }
+futures = "0.3.28"
 html-escape = "0.2.13"
 rscx-macros = { workspace = true }
 tokio = { version = "1.32.0", features = ["full"] }

rscx/src/lib.rs

@@ -3,12 +3,17 @@ pub mod axum;
 pub mod context;
 
 pub extern crate rscx_macros;
+use std::future::Future;
+
 pub use rscx_macros::*;
 
 pub extern crate typed_builder;
 
 pub extern crate html_escape;
 
+use async_trait::async_trait;
+use futures::future::join_all;
+
 pub trait CollectFragment<I>
 where
     I: Iterator,
@@ -26,3 +31,25 @@ where
         self.collect::<Vec<String>>().join("")
     }
 }
+
+#[async_trait]
+pub trait CollectFragmentAsync<I, Fut>
+where
+    I: Iterator,
+    Vec<Fut>: FromIterator<<I as Iterator>::Item>,
+    Fut: Future<Output = String>,
+{
+    async fn collect_fragment_async(self) -> String;
+}
+
+#[async_trait]
+impl<I, Fut> CollectFragmentAsync<I, Fut> for I
+where
+    I: Iterator + Send,
+    Vec<Fut>: FromIterator<<I as Iterator>::Item>,
+    Fut: Future<Output = String> + Send,
+{
+    async fn collect_fragment_async(self) -> String {
+        join_all(self.collect::<Vec<_>>()).await.join("")
+    }
+}