From 9c094fb094af1640d351f10f37ee9d870386d921 Mon Sep 17 00:00:00 2001
From: Alison Watson <marrub.xz@gmail.com>
Date: Sat, 9 Nov 2019 15:30:06 -0500
Subject: [PATCH] add SI prefixes

---
 source/common.h | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/source/common.h b/source/common.h
index 65b8133..ecab77a 100644
--- a/source/common.h
+++ b/source/common.h
@@ -23,6 +23,9 @@
 
 using namespace std::string_literals;
 
+using LitInt = unsigned long long int;
+using LitFlt = long double;
+
 inline constexpr std::nullopt_t None{std::nullopt};
 
 template<typename T>
@@ -72,6 +75,39 @@ struct IMemoryStream : public virtual MemoryStreamBuf, public std::istream {
 	}
 };
 
+#define siPrefixDivT(T, name, value) \
+	constexpr T operator "" name(T n) {return n / T(value);}
+
+#define siPrefixMulT(T, name, value) \
+	constexpr T operator "" name(T n) {return n * T(value);}
+
+#define siPrefixDiv(name, value) \
+	siPrefixDivT(LitInt, name, value) \
+	siPrefixDivT(LitFlt, name, value)
+
+#define siPrefixMul(name, value) \
+	siPrefixMulT(LitInt, name, value) \
+	siPrefixMulT(LitFlt, name, value)
+
+#define siPrefixDivMul(divName, mulName, value) \
+	siPrefixDiv(divName, value) \
+	siPrefixMul(mulName, value)
+
+siPrefixDivMul(_d,  _da,                       10)
+siPrefixDivMul(_c,  _h,                       100)
+siPrefixDivMul(_m,  _k,                     1'000)
+siPrefixDivMul(_mc, _M,                 1'000'000)
+siPrefixDivMul(_n,  _G,             1'000'000'000)
+siPrefixDivMul(_p,  _T,         1'000'000'000'000)
+siPrefixDivMul(_f,  _P,     1'000'000'000'000'000)
+siPrefixDivMul(_a,  _E, 1'000'000'000'000'000'000)
+siPrefixMul(_Ki,                     1'024)
+siPrefixMul(_Mi,                 1'048'576)
+siPrefixMul(_Gi,             1'073'741'824)
+siPrefixMul(_Ti,         1'099'511'627'776)
+siPrefixMul(_Pi,     1'125'899'906'842'624)
+siPrefixMul(_Ei, 1'152'921'504'606'846'976)
+
 static inline QString trMain(char const *sourceText,
                              char const *disambiguation = nullptr,
                              int n = -1) {