forked from rosh/MQL5Book
38 lines
1.4 KiB
MQL5
38 lines
1.4 KiB
MQL5
 | //+------------------------------------------------------------------+
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//| Unions.mq5 |
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//| Copyright 2021, MetaQuotes Ltd. |
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//| https://www.mql5.com |
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//+------------------------------------------------------------------+
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#define MAX_LONG_IN_DOUBLE 9007199254740992
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// FYI: ULONG_MAX 18446744073709551615
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union ulong2double
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{
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ulong U; // 8 bytes
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double D; // 8 bytes
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};
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ulong2double converter;
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//+------------------------------------------------------------------+
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//| Script program start function |
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//+------------------------------------------------------------------+
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void OnStart()
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{
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Print(sizeof(ulong2double)); // 8
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const ulong value = MAX_LONG_IN_DOUBLE + 1;
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double d = value; // possible loss of data due to type conversion
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ulong result = d; // possible loss of data due to type conversion
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Print(d, " / ", value, " -> ", result);
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// 9007199254740992.0 / 9007199254740993 -> 9007199254740992
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converter.U = value;
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double r = converter.D; // no conversion
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Print(r); // 4.450147717014403e-308
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Print(offsetof(ulong2double, U), " ", offsetof(ulong2double, D));
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}
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//+------------------------------------------------------------------+
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