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// Copyright (C) Parity Technologies (UK) Ltd.
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// This file is part of Polkadot.
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// Substrate is free software: you can redistribute it and/or modify

            

        

            

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// it under the terms of the GNU General Public License as published by

            

        

            

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// the Free Software Foundation, either version 3 of the License, or

            

        

            

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// (at your option) any later version.

            

        

            

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// Substrate is distributed in the hope that it will be useful,

            

        

            

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// but WITHOUT ANY WARRANTY; without even the implied warranty of

            

        

            

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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

            

        

            

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// GNU General Public License for more details.

            

        

            

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// You should have received a copy of the GNU General Public License

            

        

            

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// along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.

            

        

            

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//! Contains runtime APIs for useful conversions, such as between XCM `Location` and `AccountId`.

            

        

            

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use codec::{Decode, Encode};

            

        

            

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use scale_info::TypeInfo;

            

        

            

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use xcm::VersionedLocation;

            

        

            

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use xcm_executor::traits::ConvertLocation;

            

        

            

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sp_api::decl_runtime_apis! {

            

        

            

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	/// API for useful conversions between XCM `Location` and `AccountId`.

            

        

            

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	pub trait LocationToAccountApi<AccountId> where AccountId: Decode {

            

        

            

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		/// Converts `Location` to `AccountId`.

            

        

            

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		fn convert_location(location: VersionedLocation) -> Result<AccountId, Error>;

            

        

            

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	}

            

        

            

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}

            

        

            

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#[derive(Copy, Clone, Encode, Decode, Eq, PartialEq, Debug, TypeInfo)]

            

        

            

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pub enum Error {

            

        

            

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	/// Requested `Location` is not supported by the local conversion.

            

        

            

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	#[codec(index = 0)]

            

        

            

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	Unsupported,

            

        

            

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	/// Converting a versioned data structure from one version to another failed.

            

        

            

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	#[codec(index = 1)]

            

        

            

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	VersionedConversionFailed,

            

        

            

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}

            

        

            

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/// A helper implementation that can be used for `LocationToAccountApi` implementations.

            

        

            

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/// It is useful when you already have a `ConvertLocation<AccountId>` implementation and a default

            

        

            

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/// `Ss58Prefix`.

            

        

            

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pub struct LocationToAccountHelper<AccountId, Conversion>(

            

        

            

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	core::marker::PhantomData<(AccountId, Conversion)>,

            

        

            

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);

            

        

            

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impl<AccountId: Decode, Conversion: ConvertLocation<AccountId>>

            

        

            

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	LocationToAccountHelper<AccountId, Conversion>

            

        

            

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{

            

        

            

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	pub fn convert_location(location: VersionedLocation) -> Result<AccountId, Error> {

            

        

            

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		let location = location.try_into().map_err(|_| Error::VersionedConversionFailed)?;

            

        

            

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		Conversion::convert_location(&location).ok_or(Error::Unsupported)

            

        

            

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	}

            

        

            

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}