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diff --git a/src/script/descriptor.h b/src/script/descriptor.h
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+// Copyright (c) 2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_SCRIPT_DESCRIPTOR_H
+#define BITCOIN_SCRIPT_DESCRIPTOR_H
+
+#include <script/script.h>
+#include <script/sign.h>
+
+#include <vector>
+
+// Descriptors are strings that describe a set of scriptPubKeys, together with
+// all information necessary to solve them. By combining all information into
+// one, they avoid the need to separately import keys and scripts.
+//
+// Descriptors may be ranged, which occurs when the public keys inside are
+// specified in the form of HD chains (xpubs).
+//
+// Descriptors always represent public information - public keys and scripts -
+// but in cases where private keys need to be conveyed along with a descriptor,
+// they can be included inside by changing public keys to private keys (WIF
+// format), and changing xpubs by xprvs.
+//
+// Reference documentation about the descriptor language can be found in
+// doc/descriptors.md.
+
+/** Interface for parsed descriptor objects. */
+struct Descriptor {
+    virtual ~Descriptor() = default;
+
+    /** Whether the expansion of this descriptor depends on the position. */
+    virtual bool IsRange() const = 0;
+
+    /** Convert the descriptor back to a string, undoing parsing. */
+    virtual std::string ToString() const = 0;
+
+    /** Convert the descriptor to a private string. This fails if the provided provider does not have the relevant private keys. */
+    virtual bool ToPrivateString(const SigningProvider& provider, std::string& out) const = 0;
+
+    /** Expand a descriptor at a specified position.
+     *
+     * pos: the position at which to expand the descriptor. If IsRange() is false, this is ignored.
+     * provider: the provider to query for private keys in case of hardened derivation.
+     * output_script: the expanded scriptPubKeys will be put here.
+     * out: scripts and public keys necessary for solving the expanded scriptPubKeys will be put here (may be equal to provider).
+     */
+    virtual bool Expand(int pos, const SigningProvider& provider, std::vector<CScript>& output_scripts, FlatSigningProvider& out) const = 0;
+};
+
+/** Parse a descriptor string. Included private keys are put in out. Returns nullptr if parsing fails. */
+std::unique_ptr<Descriptor> Parse(const std::string& descriptor, FlatSigningProvider& out);
+
+#endif // BITCOIN_SCRIPT_DESCRIPTOR_H
+