Named format string parameters with format specifiers

In Ruby, you can substitute arguments into a C-style format string using the `String#%` method, like so: ``` '%.3d can be expressed in binary as %b' % [30, 30] #=> "030 can be expressed in binary as 11110" ``` `Kernel#sprintf` and `Kernel#format` behave similarly: ``` sprintf('%.3d can be expressed in binary as %b', 30, 30) #=> "030 can be expressed in binary as 11110" format('%.3d can be expressed in binary as %b', 30, 30) #=> "030 can be expressed in binary as 11110" ``` Ruby also provides the ability to use named parameters within this format string: ``` 'Hello, %{first_name} %{last_name}!' % {first_name: 'John', last_name: 'Doe'} #=> "Hello, John Doe!" ``` But is there a way to use these features together? E.g.: ``` '%{num}.3d can be expressed in binary as %{num}b' % {num: 30} # I want: "030 can be expressed in binary as 11110" # Actual: "30.3d can be expressed in binary as 30b" ``` In other words, is there a way to use flags, width specifiers, precision specifiers, and types in format strings with named parameters? What's the form of `%[flags][width][.precision]type` if I want to give the format sequence a name?