Fmt.Internal.Template

Old-style formatting a la text-format.

Documentation

>>> import Fmt

format :: FormatType r => Format -> r

An old-style formatting function taken from text-format (see Data.Text.Format). Unlike format from Data.Text.Format, it can produce String and strict Text as well (and print to console too). Also it's polyvariadic:

>>> format "{} + {} = {}" 2 2 4
2 + 2 = 4

You can use arbitrary formatters:

>>> format "0x{} + 0x{} = 0x{}" (hexF 130) (hexF 270) (hexF (130+270))
0x82 + 0x10e = 0x190

formatLn :: FormatType r => Format -> r

Like format, but adds a newline.

newtype Format

A format string. This is intentionally incompatible with other string types, to make it difficult to construct a format string by concatenating string fragments (a very common way to accidentally make code vulnerable to malicious data).

This type is an instance of IsString, so the easiest way to construct a query is to enable the OverloadedStrings language extension and then simply write the query in double quotes.

{-# LANGUAGE OverloadedStrings #-}

import Fmt

f :: Format
f = "hello {}"

The underlying type is Text, so literal Haskell strings that contain Unicode characters will be correctly handled.

Constructors

Format

Fields

• fromFormat :: Text

Instances

Eq Format

Methods

(==) :: Format -> Format -> Bool

(/=) :: Format -> Format -> Bool

Ord Format

Methods

compare :: Format -> Format -> Ordering

(<) :: Format -> Format -> Bool

(<=) :: Format -> Format -> Bool

(>) :: Format -> Format -> Bool

(>=) :: Format -> Format -> Bool

max :: Format -> Format -> Format

min :: Format -> Format -> Format

Show Format

Methods

showsPrec :: Int -> Format -> ShowS

show :: Format -> String

showList :: [Format] -> ShowS

IsString Format

Methods

fromString :: String -> Format

Semigroup Format

Methods

(<>) :: Format -> Format -> Format

sconcat :: NonEmpty Format -> Format

stimes :: Integral b => b -> Format -> Format

Monoid Format

Methods

mempty :: Format

mappend :: Format -> Format -> Format

mconcat :: [Format] -> Format

renderFormat :: Format -> [Builder] -> Builder

Render a format string and arguments to a Builder.

zipParams :: [Builder] -> [Builder] -> Builder

crack :: Format -> [Builder]

class FormatType r where

Something like PrintfType in Text.Printf.

Minimal complete definition

format'

Methods

format' :: Format -> [Builder] -> r

Instances

FromBuilder r => FormatType r

Methods

format' :: Format -> [Builder] -> r

(Buildable a, FormatType r) => FormatType (a -> r)

Methods

format' :: Format -> [Builder] -> a -> r