Use the standard fixed-size integer types directly

[libs/core.git] / source / strings / lexicalcast.cpp

diff --git a/source/strings/lexicalcast.cpp b/source/strings/lexicalcast.cpp
index 782f4a8537adb05583c6e45e68c6b80620439142..2b84d9bbbcdaa4e93af36d15d6bb5063807f7ef6 100644 (file)
--- a/source/strings/lexicalcast.cpp
+++ b/source/strings/lexicalcast.cpp
@@ -1,4 +1,5 @@
 #include <cmath>
+#include <cstdint>
 #include <limits>
 #include "format.h"
 #include "lexicalcast.h"
@@ -9,26 +10,8 @@ namespace {
 
 using namespace Msp;
 
-template<typename T>
-struct IsSigned
-{ enum { result = !(static_cast<T>(-1)>0) }; };
-
-template<typename T, bool f = (sizeof(T)>sizeof(unsigned long))>
-struct Temporary
-{ typedef unsigned long Type; };
-
-template<typename T>
-struct Temporary<T, true>
-{
-#ifdef WIN32
-       typedef __int64 Type;
-#else
-       typedef unsigned long long Type;
-#endif
-};
-
 /* Helper to avoid warnings about an unsigned type never being < 0 */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct IsNegative
 { static bool eval(T v) { return v<0; } };
 
@@ -36,9 +19,17 @@ template<typename T>
 struct IsNegative<T, false>
 { static bool eval(T) { return false; } };
 
+template<typename T, bool f = is_signed<T>::value>
+struct Negate
+{ static T eval(T v) { return -v; } };
+
+template<typename T>
+struct Negate<T, false>
+{ static T eval(T v) { return (~v)+1; } };
+
 /* Helper to avoid errors about ambiguous function calls since there are no
 overloads of abs for unsigned types */
-template<typename T, bool f = IsSigned<T>::result>
+template<typename T, bool f = is_signed<T>::value>
 struct Absolute
 { static T eval(T v) { return v<0 ? -v : v; } };
 
@@ -72,7 +63,7 @@ char *int_to_str(T v, const Fmt &f, char *end)
        const char *digits = (f.get_uppercase() ? udigits : ldigits);
        if(v)
        {
-               typename Temporary<T>::Type w = Absolute<T>::eval(v);
+               typename std::make_unsigned<T>::type w = Absolute<T>::eval(v);
                while(w)
                {
                        *--ptr = digits[w%base];
@@ -121,18 +112,18 @@ string int_to_str(T v, const Fmt &f)
 }
 
 template<typename T>
-T str_to_int(const std::string &s, const Fmt &f)
+T str_to_int(const string &s, const Fmt &f)
 {
        if(s.empty())
                throw lexical_error("conversion of '' to integer");
 
-       std::string::const_iterator i = s.begin();
+       auto i = s.begin();
 
        // See if the input starts with a sign
        bool neg = false;
        if(*i=='-')
        {
-               if(!IsSigned<T>::result)
+               if(is_unsigned<T>::value)
                        throw lexical_error(format("conversion of '%s' to unsigned integer", s));
                neg = true;
                ++i;
@@ -187,7 +178,7 @@ T str_to_int(const std::string &s, const Fmt &f)
        }
 
        if(neg)
-               result = -result;
+               result = Negate<T>::eval(result);
 
        return result;
 }
@@ -250,7 +241,7 @@ string flt_to_str(T v, const Fmt &f)
        if(w>=10)
        {
                long double div = 1;
-               while(div*10<w)
+               while(div*10<=w)
                {
                        ++exp;
                        div *= 10;
@@ -270,6 +261,7 @@ string flt_to_str(T v, const Fmt &f)
 
        // Decide how to format the number
        unsigned digits;
+       unsigned leading_zeroes = 0;
        unsigned point = 1;
        bool showexp = false;
        if(mode==Fmt::FIXED)
@@ -292,15 +284,16 @@ string flt_to_str(T v, const Fmt &f)
                }
                else
                {
-                       point = max(exp, 0)+1;
                        if(exp<0)
-                               digits += -exp;
+                               leading_zeroes = -exp;
+                       else
+                               point = exp+1;
                }
        }
 
        // Apply rounding
        w += 5.0l/pow(10.0l, static_cast<long double>(digits));
-       if(w>10)
+       if(w>=10)
        {
                // Rounding bumped us to the next exponent, deal with it
                w /= 10;
@@ -311,13 +304,19 @@ string flt_to_str(T v, const Fmt &f)
                }
                if(!showexp)
                {
-                       ++digits;
-                       ++point;
+                       if(mode==Fmt::FIXED)
+                               ++digits;
+                       if(leading_zeroes)
+                               --leading_zeroes;
+                       else
+                               ++point;
                }
                else
                        ++exp;
        }
 
+       digits += leading_zeroes;
+
        // Create a buffer and start from the end
        unsigned size = max(f.get_width(), digits+8);
        char *buf = new char[size];
@@ -339,14 +338,17 @@ string flt_to_str(T v, const Fmt &f)
        {
                if(i==point)
                        *mptr++ = '.';
-               if(showexp || static_cast<int>(i)>=-exp)
+               if(!leading_zeroes)
                {
                        int digit = static_cast<int>(w);
                        *mptr++ = '0'+digit;
                        w = (w-digit)*10;
                }
                else
+               {
                        *mptr++ = '0';
+                       --leading_zeroes;
+               }
        }
 
        if(f.get_showpoint())
@@ -391,7 +393,7 @@ T str_to_flt(const string &s, const Fmt &)
        if(s.empty())
                throw lexical_error("conversion of '' to floating-point");
 
-       std::string::const_iterator i = s.begin();
+       auto i = s.begin();
 
        // See if the input starts with a sign
        bool neg = false;
@@ -473,6 +475,7 @@ namespace Msp {
 
 void LexicalConverter::result(const string &s)
 {
+       filled = true;
        if(s.size()<fmt.get_width())
        {
                if(fmt.get_align()==Fmt::RIGHT)
@@ -484,6 +487,13 @@ void LexicalConverter::result(const string &s)
                buf = s;
 }
 
+const string &LexicalConverter::get() const
+{
+       if(!filled)
+               throw lexical_error("conversion not performed");
+       return buf;
+}
+
 
 /*** operator<< ***/
 
@@ -547,7 +557,7 @@ void operator<<(LexicalConverter &c, const char *s)
 { c.result(str_to_str(s, c.get_fmt())); }
 
 void operator<<(LexicalConverter &c, const void *p)
-{ c.result(int_to_str(reinterpret_cast<unsigned long>(p), c.get_fmt())); }
+{ c.result(int_to_str(reinterpret_cast<intptr_t>(p), c.get_fmt())); }
 
 
 /*** operator>> ***/
@@ -558,7 +568,7 @@ void operator>>(const LexicalConverter &c, char &v)
                v = str_to_int<char>(c.get(), c.get_fmt());
        else
        {
-               const std::string &s = c.get();
+               const string &s = c.get();
                if(s.empty())
                        throw lexical_error("conversion of '' to character");
                if(s.size()>1)