format: Check if the scientific form is to be used

This commit is contained in:
Eugen Wissner 2017-11-25 14:59:27 +01:00
parent ac317aa9d6
commit fbf6ec5250

View File

@ -501,6 +501,19 @@ Zeroed:
return result[0 .. length]; return result[0 .. length];
} }
private void leadSign(bool negative, ref char[8] sign)
{
if (negative)
{
sign[0] = 1;
sign[1] = '-';
}
else
{
sign[0] = 0;
}
}
package(tanya) String format(string fmt, Args...)(Args args) package(tanya) String format(string fmt, Args...)(Args args)
{ {
String ret; String ret;
@ -535,12 +548,56 @@ package(tanya) String format(string fmt, Args...)(Args args)
{ {
int precision = 6; int precision = 6;
bool negative; bool negative;
int decimalPos; int decimalPoint;
uint l;
char[512] num; char[512] num;
char[8] tail;
char[8] lead;
// Read the double into a string // Read the double into a string
const(char)[] sn = real2String(args[0], num, decimalPos, negative); const(char)[] sn = real2String(args[0], num, decimalPoint, negative);
uint n = precision;
// Clamp the precision and delete extra zeros after clamp.
if (sn.length > (cast(uint) precision))
{
sn = sn[0 .. precision];
}
while (sn.length > 1 && precision != 0 && sn[$ - 1] == '0')
{
--precision;
sn = sn[0 .. $ - 1];
}
// Should the scientific notation be used?
if (decimalPoint <= -4 || decimalPoint > (cast(int) n))
{
if (precision > (cast(int) sn.length))
{
precision = cast(int) (sn.length - 1);
}
else if (precision != 0)
{
--precision; // There is 1 digit before the decimal point.
}
}
else
{
if (decimalPoint > 0)
{
precision = decimalPoint < (cast(int) sn.length)
? cast(int) (sn.length - decimalPoint)
: 0;
}
else if (precision > (cast(int) sn.length))
{
precision = -decimalPoint + cast(int) sn.length;
}
else
{
precision = -decimalPoint + precision;
}
}
} }
else else
{ {