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// This file is part of Substrate.
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// Copyright (C) Parity Technologies (UK) Ltd.
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// SPDX-License-Identifier: Apache-2.0
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// 	http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//! Lowest-abstraction level for the Substrate runtime: just exports useful primitives from std
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//! or client/alloc to be used with any code that depends on the runtime.
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#![cfg_attr(not(feature = "std"), no_std)]
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#![cfg_attr(
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	feature = "std",
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	doc = "Substrate runtime standard library as compiled when linked with Rust's standard library."
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)]
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#![cfg_attr(
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	not(feature = "std"),
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	doc = "Substrate's runtime standard library as compiled without Rust's standard library."
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)]
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/// Initialize a key-value collection from array.
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///
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/// Creates a vector of given pairs and calls `collect` on the iterator from it.
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/// Can be used to create a `HashMap`.
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#[macro_export]
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macro_rules! map {
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	($( $name:expr => $value:expr ),* $(,)? ) => (
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		vec![ $( ( $name, $value ) ),* ].into_iter().collect()
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	)
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}
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/// Feature gate some code that should only be run when `std` feature is enabled.
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///
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/// # Example
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///
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/// ```
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/// use sp_std::if_std;
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///
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/// if_std! {
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///     // This code is only being compiled and executed when the `std` feature is enabled.
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///     println!("Hello native world");
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/// }
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/// ```
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#[cfg(feature = "std")]
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#[macro_export]
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macro_rules! if_std {
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	( $( $code:tt )* ) => {
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		$( $code )*
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	}
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}
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#[cfg(not(feature = "std"))]
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#[macro_export]
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macro_rules! if_std {
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	( $( $code:tt )* ) => {};
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}
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#[cfg(feature = "std")]
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include!("../with_std.rs");
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#[cfg(not(feature = "std"))]
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include!("../without_std.rs");
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/// A target for `core::write!` macro - constructs a string in memory.
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#[derive(Default)]
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pub struct Writer(vec::Vec<u8>);
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impl fmt::Write for Writer {
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	fn write_str(&mut self, s: &str) -> fmt::Result {
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		self.0.extend(s.as_bytes());
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		Ok(())
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	}
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}
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impl Writer {
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	/// Access the content of this `Writer` e.g. for printout
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	pub fn inner(&self) -> &vec::Vec<u8> {
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		&self.0
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	}
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	/// Convert into the content of this `Writer`
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	pub fn into_inner(self) -> vec::Vec<u8> {
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		self.0
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	}
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}
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/// Prelude of common useful imports.
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///
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/// This should include only things which are in the normal std prelude.
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pub mod prelude {
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	pub use crate::{
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		borrow::ToOwned,
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		boxed::Box,
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		clone::Clone,
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		cmp::{Eq, PartialEq, Reverse},
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		iter::IntoIterator,
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		vec::Vec,
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	};
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	// Re-export `vec!` macro here, but not in `std` mode, since
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	// std's prelude already brings `vec!` into the scope.
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	#[cfg(not(feature = "std"))]
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	pub use crate::vec;
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}