static u32string prefix() {return u32string(U"kilo");}
static u32string prefix() {return u32string(U"hecto");}
static u32string symbol() {return u32string(1, U'k');}
static u32string symbol() {return u32string(U"da");}
static u32string prefix() {return u32string(U"deca");}
static u32string prefix() {return u32string(U"milli");}
static u32string prefix() {return u32string(U"centi");}
static u32string prefix() {return u32string(U"micro");}
static u32string prefix() {return u32string(U"nano");}
static u32string prefix() {return u32string(U"pico");}
static u32string prefix() {return u32string(U"femto");}
std::pair<bool, u32string>
build_escaped_characters
(
Iterator& current,
const Iterator& end
)
{
std::string building;
bool error = false;
int to_read = 0;
while (*current == '\\' && error == false)
{
++current;
char32_t c = *current;
switch(c)
{
case 'U':
to_read = 8;
++current;
break;
case 'u':
to_read = 4;
++current;
break;
case 'x':
to_read = 2;
++current;
break;
case 'n':
building += "\n";
++current;
break;
case 'r':
building += "\r";
++current;
break;
case 't':
building += "\t";
++current;
break;
case '\'':
building += "\'";
++current;
break;
case '\"':
building += "\"";
++current;
break;
case '\\':
building += "\\";
++current;
break;
default:
//invalid control character
error = true;
break;
}
//read the requested number of characters
std::string chars;
if (to_read > 0)
{
while (to_read > 0 && current != end && *current != '\'')
{
c = *current;
if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F'))
{
chars += c;
}
else
{
break;
}
--to_read;
++current;
}
}
//if we didn't read everything then error
if (to_read != 0)
{
error = true;
}
else
{
uint32_t value = 0;
for (char c : chars)
{
if (c >= '0' && c <= '9')
{
value = value * 16 + (c - '0');
}
else
{
value = value * 16 + (c - 'A' + 10);
}
}
//it was a byte if it was two characters, otherwise it was a whole
//character
if (chars.length() == 2)
{
building += char(value & 0xFF);
}
else
{
building += utf32_to_utf8(u32string(1, value));
}
}
}
u32string u32result = utf8_to_utf32(building);
return std::make_pair(!error, u32result);
}
