Text.Printf.Safe.QQ

Documentation

fmt :: QuasiQuoter

Quasiquoter for formatter. It supprots escape sequence. Formatter is prefixed by % and you can use %{hoge} to antiquotation.

>>> :set -XQuasiQuotes
>>> printf [fmt|Answer is: %d and %S|] 42 True
"Answer is: 42 and True"

>>> printf [fmt|%02d%% of people answers %{show . not}.\n|] 4 False
"04% of people answers True.\n"

Predefined formatters:

%%

outputs %.

%d

formats Integral value in decimal.

%nd

same as above, but padding with ' ' (space) to n digits.

%0nd

same as above, but padding with '0' to n digits.

%b, %o, %h, %H

formats Integrals in binary, octet, hex and HEX resp. Padding options can be specified as %d.

%f

formats Real value with show function.

%s

embeds String value.

%S

embeds Show instances.

%{expr}, where expr is a Haskell expression of type a -> String

Antiquote. This formats corresponding argument by passing to expr.