87659a17d0
Compared to the python version, this also does type checking and error handling, so it's slightly longer, however, it's still comfortably under 500 lines. Relanding with more explicit type conversions.
44 lines
1.5 KiB
C++
44 lines
1.5 KiB
C++
// A bare-bones llvm::Optional reimplementation.
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template <typename T> struct MyOptionalStorage {
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MyOptionalStorage(T val) : value(val), hasVal(true) {}
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MyOptionalStorage() {}
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T value;
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bool hasVal = false;
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};
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template <typename T> struct MyOptional {
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MyOptionalStorage<T> Storage;
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MyOptional(T val) : Storage(val) {}
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MyOptional() {}
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T &operator*() { return Storage.value; }
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};
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void stop() {}
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int main(int argc, char **argv) {
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MyOptional<int> x, y = 42;
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stop(); // break here
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return *y;
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}
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// Produced from the assembler in
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// Shell/ScriptInterpreter/Python/Inputs/FormatterBytecode/formatter.py
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__attribute__((used, section("__DATA_CONST,__lldbformatters"))) unsigned char
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_MyOptional_type_summary[] =
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"\x01" // version
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"\xa4" // record size
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"\x01" // record size
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"\x10" // type name size
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"^MyOptional<.+>$" // type name
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"\x00" // flags
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"\x00" // sig_summary
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"\x8d" // program size
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"\x01" // program size
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"\x1\x22\x7Storage#\x12\x60\x1,C\x10\x1\x5\x11\x2\x1\x22\x6hasVal#"
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"\x12\x60\x1,\x10\x1e\x2\x22\x1b<could not read MyOptional>\x10G#!\x60 "
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"\x0P\x10\x6\x22\x4None\x10\x36\x1#\x15\x60 "
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"\x0#\x16\x60\x5\x22\x5value#\x12\x60\x5#\x17\x60\x1,"
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"\x10\x6\x22\x4None\x10\x11\x1#\x0\x60\x1#R\x60\x10\x3# "
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"\x60\x10\x1\x2\x12\x12\x12\x12"; // summary function
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