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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

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1// Copyright (c) 2019-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef BITCOIN_UTIL_MACROS_H
6#define BITCOIN_UTIL_MACROS_H
7
8#define PASTE(x, y) x ## y
9#define PASTE2(x, y) PASTE(x, y)
10
11#define BITCOIN_UNIQUE_NAME(name) PASTE2(name, __COUNTER__)
12
13/**
14 * Converts the parameter X to a string after macro replacement on X has been performed.
15 * Don't merge these into one macro!
16 */
17#define STRINGIZE(X) DO_STRINGIZE(X)
18#define DO_STRINGIZE(X) #X
19
20#endif // BITCOIN_UTIL_MACROS_H
21

FILE GUIDE · KEY SECTIONS

Expansion helpers for names and string literals

These macros provide token pasting, unique local names and stringification after macro expansion.

Line 8 ↗

Use two expansion stages when pasting tokens

PASTE2 expands arguments before PASTE joins them. BITCOIN_UNIQUE_NAME combines a prefix with __COUNTER__, helping repeated macros introduce distinct local identifiers.

Line 17 ↗

Stringify the expanded argument

STRINGIZE forwards to DO_STRINGIZE so macro substitution happens before the # operator produces a string literal. Collapsing the two definitions changes expansion behavior. None of these macros creates a globally stable identifier.

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