a format string containing a single format specifier
character type of fmt
A FormatSpec with the format specifier parsed.
A FormatException when the format string contains no format specifier or more than a single format specifier or when the format specifier is malformed.
import std.array : appender; import std.format.write : formatValue; auto spec = singleSpec("%10.3e"); auto writer = appender!string(); writer.formatValue(42.0, spec); assert(writer.data == " 4.200e+01");
Helper function that returns a FormatSpec for a single format specifier.