Returns a decimal-point string-representation of this.
Converts this to a Decimal before computing the string representation.
If the absolute value of this is greater or equal to 10^21 then this
methods returns an exponential representation computed by
this.toStringAsExponential(). Otherwise the result
is the closest string representation with exactly fractionDigits digits
after the decimal point. If fractionDigits equals 0 then the decimal
point is omitted.
Parses a string containing a number literal into a number.
The method first tries to read the input as integer (similar to
int.parse without a radix).
If that fails, it tries to parse the input as a decimal (similar to
Decimal.parse).
If that fails too, it throws FormatException.