cpp / expert
Snippet
Bitmask-Driven Control Logic
Using bitwise operators and enum classes to manage complex control flow states efficiently. This approach packs multiple boolean flags into a single byte, optimizing both memory and branch prediction.
snippet.cpp
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#include <cstdint>enum class Permissions : uint8_t {Read = 1 << 0, // 0001Write = 1 << 1, // 0010Exec = 1 << 2 // 0100};inline bool has_permission(uint8_t mask, Permissions p) {return (mask & static_cast<uint8_t>(p)) != 0;}void process_request(uint8_t mask) {if (has_permission(mask, Permissions::Read)) {// Execute read logic}if (has_permission(mask, Permissions::Write)) {// Execute write logic}}
Breakdown
1
1 << 0
Uses the bit-shift operator to define unique power-of-two values for each flag.
2
mask & static_cast<uint8_t>(p)
Performs a bitwise AND to check if a specific bit is set within the flag mask.