From 280eb2239a2fcaa83a35ae6fb1ce62fe35a1e222 Mon Sep 17 00:00:00 2001
From: "Tobin C. Harding" <me@tobin.cc>
Date: Fri, 17 Jan 2025 11:51:20 +1100
Subject: [PATCH] io: Remove the impl_write macro

We have found calling macros from other crates to be error prone,
especially when they involve feature gates. Furthermore the `impl_write`
macro is trivial to write, users can just write it in the crate that
needs it.

Remove the macro. While we are at it point users to the examples in
`bitcoin/examples/io.rs` for usage of the `io` crate.
---
 io/src/lib.rs    |  4 +++-
 io/src/macros.rs | 58 ------------------------------------------------
 2 files changed, 3 insertions(+), 59 deletions(-)
 delete mode 100644 io/src/macros.rs

diff --git a/io/src/lib.rs b/io/src/lib.rs
index 0e1d33126..71e71bb7e 100644
--- a/io/src/lib.rs
+++ b/io/src/lib.rs
@@ -9,6 +9,9 @@
 //!
 //! These traits are not one-for-one drop-ins, but are as close as possible while still implementing
 //! `std::io`'s traits without unnecessary complexity.
+//!
+//! For examples of how to use and implement the types and traits in this crate see `io.rs` in the
+//! `github.com/rust-bitcoin/rust-bitcoin/bitcoin/examples/` directory.
 
 #![cfg_attr(not(feature = "std"), no_std)]
 // Experimental features we need.
@@ -28,7 +31,6 @@ extern crate alloc;
 #[cfg(feature = "std")]
 mod bridge;
 mod error;
-mod macros;
 
 #[cfg(all(not(feature = "std"), feature = "alloc"))]
 use alloc::vec::Vec;
diff --git a/io/src/macros.rs b/io/src/macros.rs
deleted file mode 100644
index 55df18aa7..000000000
--- a/io/src/macros.rs
+++ /dev/null
@@ -1,58 +0,0 @@
-// SPDX-License-Identifier: CC0-1.0
-
-/// Implements [`crate::Write`] for `$ty`.
-// See below for docs (docs.rs build enables all features).
-#[cfg(not(feature = "std"))]
-#[macro_export]
-macro_rules! impl_write {
-    ($ty: ty, $write_fn: expr, $flush_fn: expr $(, $bounded_ty: ident : $bounds: path),*) => {
-        impl<$($bounded_ty: $bounds),*> $crate::Write for $ty {
-            #[inline]
-            fn write(&mut self, buf: &[u8]) -> $crate::Result<usize> {
-                $write_fn(self, buf)
-            }
-            #[inline]
-            fn flush(&mut self) -> $crate::Result<()> {
-                $flush_fn(self)
-            }
-        }
-    }
-}
-
-/// Implements [`crate::Write`] for `$ty`.
-///
-/// Also implements [`std::io::Write`] for `$ty` if `bitcoin_io` has the `std` feature enabled.
-///
-/// # Arguments
-///
-/// * `$ty` - the type used to implement the two traits.
-/// * `write_fn` - the function called by the `Write::write` trait method.
-/// * `flush_fn` - the function called by the `Write::flush` trait method.
-/// * `$bounded_ty: $bounds` - optional trait bounds if required.
-#[cfg(feature = "std")]
-#[macro_export]
-macro_rules! impl_write {
-    ($ty: ty, $write_fn: expr, $flush_fn: expr $(, $bounded_ty: ident : $bounds: path),*) => {
-        impl<$($bounded_ty: $bounds),*> std::io::Write for $ty {
-            #[inline]
-            fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
-                $write_fn(self, buf)
-            }
-            #[inline]
-            fn flush(&mut self) -> std::io::Result<()> {
-                $flush_fn(self)
-            }
-        }
-
-        impl<$($bounded_ty: $bounds),*> $crate::Write for $ty {
-            #[inline]
-            fn write(&mut self, buf: &[u8]) -> $crate::Result<usize> {
-                $write_fn(self, buf)
-            }
-            #[inline]
-            fn flush(&mut self) -> $crate::Result<()> {
-                $flush_fn(self)
-            }
-        }
-    }
-}