The ~R directive, which I discussed in “Character and Integer Directives,” when used with no base specified, prints numbers as English words or Roman numerals. When used with no prefix parameter and no modifiers, it emits the number in words as a cardinal number.

With the colon modifier, it emits the number as an ordinal.

(format nil "~:r" 1234) ==> "one thousand two hundred thirty-fourth"

For numbers too large to be represented in the given form, ~R behaves like ~D.

To help you generate messages with words properly pluralized, **FORMAT** provides the ~P directive, which simply emits an s unless the corresponding argument is 1.

(format nil "file~p" 10) ==> "files"

With the at-sign modifier, which can be combined with the colon modifier, ~P emits either y or ies.

(format nil "~r famil~:@p" 1)  ==> "one family"
(format nil "~r famil~:@p" 10) ==> "ten families"
(format nil "~r famil~:@p" 0)  ==> "zero families"

Obviously, ~P can’t solve all pluralization problems and is no help for generating messages in other languages, but it’s handy for the cases it does handle. And the directive, which I’ll discuss in a moment, gives you a more flexible way to conditionalize parts of **FORMAT**‘s output.

You can modify ~( with an at sign to make it capitalize the first word in a section of text, with a colon to make it to capitalize all words, and with both modifiers to convert all text to uppercase. (A word for the purpose of this directive is a sequence of alphanumeric characters delimited by nonalphanumeric characters or the ends of the text.)

(format nil "~@(~a~)" "tHe Quick BROWN foX")  ==> "The quick brown fox"
(format nil "~:(~a~)" "tHe Quick BROWN foX")  ==> "The Quick Brown Fox"