stache-2.3.4: Mustache templates for Haskell

Copyright | © 2016–present Stack Builders
License | BSD 3 clause
Maintainer | Mark Karpov <markkarpov92@gmail.com>
Stability | experimental
Portability | portable
Safe Haskell | None
Language | Haskell2010

Text.Mustache

Contents

- Types
- Compiling
- Rendering

Description

This is a Haskell implementation of Mustache templates. The implementation conforms to the version 1.1.3 of the official Mustache specification https://github.com/mustache/spec. It has a minimal but complete API—three functions to compile templates (from directory, from file, and from lazy text) and one to render them.

The implementation uses Megaparsec parsing library to parse the templates which results in high-quality error messages.

For rendering you only need to create Aeson's `Value` that is used for interpolation of template variables. Since the library re-uses Aeson's instances and most data types in the Haskell ecosystem are instances of classes like `ToJSON`, the process is simple for the end user.

Template Haskell helpers for compilation of templates at compile time are available in the Text.Mustache.Compile.TH module.

One feature that is not currently supported is lambdas. The feature is marked as optional in the spec and can be emulated via processing of parsed template representation. The decision to drop lambdas is intentional, for the sake of simplicity and better integration with Aeson.

Here is an example of basic usage:

    {-# LANGUAGE OverloadedStrings #-}

    module Main (main) where

    import Data.Aeson
    import Data.Text
    import Text.Megaparsec
    import Text.Mustache
    import qualified Data.Text.Lazy.IO as TIO

    main :: IO ()
    main = do
      let res = compileMustacheText "foo"
            "Hi, {{name}}! You have:\n{{#things}}\n  * {{.}}\n{{/things}}\n"
      case res of
        Left bundle -> putStrLn (errorBundlePretty bundle)
        Right template -> TIO.putStr $ renderMustache template $ object
          [ "name"   .= ("John" :: Text)
          , "things" .= ["pen" :: Text, "candle", "egg"]
          ]

If I run the program, it prints the following:

    Hi, John! You have:
      * pen
      * candle
      * egg

For more information about Mustache templates the following links may be helpful:

- The official Mustache site: https://mustache.github.io/
- The manual: https://mustache.github.io/mustache.5.html
- The specification: https://github.com/mustache/spec
- Stack Builders Stache tutorial: https://www.stackbuilders.com/tutorials/haskell/mustache-templates/

Synopsis

- data Template = Template {
  - templateActual :: PName
  - templateCache :: Map PName [Node]
  }
- data Node
  - = TextBlock Text
  - | EscapedVar Key
  - | UnescapedVar Key
  - | Section Key [Node]
  - | InvertedSection Key [Node]
  - | Partial PName (Maybe Pos)
- newtype Key = Key {
  - unKey :: [Text]
  }
- newtype PName = PName {
  - unPName :: Text
  }
- newtype MustacheException = MustacheParserException (ParseErrorBundle Text Void)
- data MustacheWarning
  - = MustacheVariableNotFound Key
  - | MustacheDirectlyRenderedValue Key
- displayMustacheWarning :: MustacheWarning -> String
- compileMustacheDir :: MonadIO m => PName -> FilePath -> m Template
- compileMustacheDir' :: MonadIO m => (FilePath -> Bool) -> PName -> FilePath -> m Template
- compileMustacheFile :: MonadIO m => FilePath -> m Template
- compileMustacheText :: PName -> Text -> Either (ParseErrorBundle Text Void) Template
- renderMustache :: Template -> Value -> Text
- renderMustacheW :: Template -> Value -> ([MustacheWarning], Text)

# Types

data Template #

Mustache template as the name of the “top-level” template and a collection of all available templates (partials).

`Template` is a `Semigroup`. This means that you can combine `Template`s (and their caches) using the `(`<>`)` operator, the resulting `Template` will have the same currently selected template as the left one. Union of caches is also left-biased.

Constructors

Template |
Fields templateActual :: PName The name of the currently “selected” template. templateCache :: Map PName [Node] A collection of all templates that are available for interpolation (as partials). The top-level one is also contained here and the “focus” can be switched easily by modifying `templateActual`.

#### Instances

Instances details

Semigroup Template # |
Instance details Defined in Text.Mustache.Type Methods (<>) :: Template -> Template -> Template # sconcat :: NonEmpty Template -> Template # stimes :: Integral b => b -> Template -> Template #
Data Template # |
Instance details Defined in Text.Mustache.Type Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Template -> c Template # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Template # toConstr :: Template -> Constr # dataTypeOf :: Template -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Template) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Template) # gmapT :: (forall b. Data b => b -> b) -> Template -> Template # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Template -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Template -> r # gmapQ :: (forall d. Data d => d -> u) -> Template -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Template -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Template -> m Template # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Template -> m Template # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Template -> m Template #
Generic Template # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep Template |
Instance details Defined in Text.Mustache.Type type Rep Template = D1 ('MetaData "Template" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) (C1 ('MetaCons "Template" 'PrefixI 'True) (S1 ('MetaSel ('Just "templateActual") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PName) :*: S1 ('MetaSel ('Just "templateCache") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Map PName [Node]))))
Methods from :: Template -> Rep Template x # to :: Rep Template x -> Template #
Show Template # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> Template -> ShowS # show :: Template -> String # showList :: [Template] -> ShowS #
Eq Template # |
Instance details Defined in Text.Mustache.Type Methods (==) :: Template -> Template -> Bool # (/=) :: Template -> Template -> Bool #
Ord Template # |
Instance details Defined in Text.Mustache.Type Methods compare :: Template -> Template -> Ordering # (<) :: Template -> Template -> Bool # (<=) :: Template -> Template -> Bool # (>) :: Template -> Template -> Bool # (>=) :: Template -> Template -> Bool # max :: Template -> Template -> Template # min :: Template -> Template -> Template #
Lift Template # | Since: 2.1.0
Instance details Defined in Text.Mustache.Type Methods lift :: Quote m => Template -> m Exp # liftTyped :: forall (m :: Type -> Type). Quote m => Template -> Code m Template #
type Rep Template # |
Instance details Defined in Text.Mustache.Type type Rep Template = D1 ('MetaData "Template" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) (C1 ('MetaCons "Template" 'PrefixI 'True) (S1 ('MetaSel ('Just "templateActual") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PName) :*: S1 ('MetaSel ('Just "templateCache") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Map PName [Node]))))

data Node #

A structural element of a template.

Constructors

TextBlock Text | Plain text contained between tags
EscapedVar Key | HTML-escaped variable
UnescapedVar Key | Unescaped variable
Section Key [Node] | Mustache section
InvertedSection Key [Node] | Inverted section
Partial PName (Maybe Pos) | Partial with indentation level (`Nothing` means it was inlined)

#### Instances

Instances details

Data Node # |
Instance details Defined in Text.Mustache.Type Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Node -> c Node # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Node # toConstr :: Node -> Constr # dataTypeOf :: Node -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Node) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Node) # gmapT :: (forall b. Data b => b -> b) -> Node -> Node # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Node -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Node -> r # gmapQ :: (forall d. Data d => d -> u) -> Node -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Node -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Node -> m Node # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Node -> m Node # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Node -> m Node #
Generic Node # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep Node |
Instance details Defined in Text.Mustache.Type type Rep Node = D1 ('MetaData "Node" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) ((C1 ('MetaCons "TextBlock" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)) :+: (C1 ('MetaCons "EscapedVar" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)) :+: C1 ('MetaCons "UnescapedVar" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)))) :+: (C1 ('MetaCons "Section" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Node])) :+: (C1 ('MetaCons "InvertedSection" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Node])) :+: C1 ('MetaCons "Partial" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PName) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Maybe Pos))))))
Methods from :: Node -> Rep Node x # to :: Rep Node x -> Node #
Show Node # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> Node -> ShowS # show :: Node -> String # showList :: [Node] -> ShowS #
Eq Node # |
Instance details Defined in Text.Mustache.Type Methods (==) :: Node -> Node -> Bool # (/=) :: Node -> Node -> Bool #
Ord Node # |
Instance details Defined in Text.Mustache.Type Methods compare :: Node -> Node -> Ordering # (<) :: Node -> Node -> Bool # (<=) :: Node -> Node -> Bool # (>) :: Node -> Node -> Bool # (>=) :: Node -> Node -> Bool # max :: Node -> Node -> Node # min :: Node -> Node -> Node #
Lift Node # | Since: 2.1.0
Instance details Defined in Text.Mustache.Type Methods lift :: Quote m => Node -> m Exp # liftTyped :: forall (m :: Type -> Type). Quote m => Node -> Code m Node #
type Rep Node # |
Instance details Defined in Text.Mustache.Type type Rep Node = D1 ('MetaData "Node" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) ((C1 ('MetaCons "TextBlock" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)) :+: (C1 ('MetaCons "EscapedVar" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)) :+: C1 ('MetaCons "UnescapedVar" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)))) :+: (C1 ('MetaCons "Section" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Node])) :+: (C1 ('MetaCons "InvertedSection" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Node])) :+: C1 ('MetaCons "Partial" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 PName) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Maybe Pos))))))

newtype Key #

Identifier for values to interpolate.

The representation is the following:

- `[]`—empty list means implicit iterators;
- `[text]`—single key is a normal identifier;
- `[text1, text2]`—multiple keys represent dotted names.

Constructors

Key |
Fields unKey :: [Text]

#### Instances

Instances details

NFData Key # |
Instance details Defined in Text.Mustache.Type Methods rnf :: Key -> () #
Monoid Key # |
Instance details Defined in Text.Mustache.Type Methods mempty :: Key # mappend :: Key -> Key -> Key # mconcat :: [Key] -> Key #
Semigroup Key # |
Instance details Defined in Text.Mustache.Type Methods (<>) :: Key -> Key -> Key # sconcat :: NonEmpty Key -> Key # stimes :: Integral b => b -> Key -> Key #
Data Key # |
Instance details Defined in Text.Mustache.Type Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Key -> c Key # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Key # toConstr :: Key -> Constr # dataTypeOf :: Key -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Key) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Key) # gmapT :: (forall b. Data b => b -> b) -> Key -> Key # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Key -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Key -> r # gmapQ :: (forall d. Data d => d -> u) -> Key -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Key -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Key -> m Key # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Key -> m Key # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Key -> m Key #
Generic Key # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep Key |
Instance details Defined in Text.Mustache.Type type Rep Key = D1 ('MetaData "Key" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "Key" 'PrefixI 'True) (S1 ('MetaSel ('Just "unKey") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Text])))
Methods from :: Key -> Rep Key x # to :: Rep Key x -> Key #
Show Key # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> Key -> ShowS # show :: Key -> String # showList :: [Key] -> ShowS #
Eq Key # |
Instance details Defined in Text.Mustache.Type Methods (==) :: Key -> Key -> Bool # (/=) :: Key -> Key -> Bool #
Ord Key # |
Instance details Defined in Text.Mustache.Type Methods compare :: Key -> Key -> Ordering # (<) :: Key -> Key -> Bool # (<=) :: Key -> Key -> Bool # (>) :: Key -> Key -> Bool # (>=) :: Key -> Key -> Bool # max :: Key -> Key -> Key # min :: Key -> Key -> Key #
Lift Key # | Since: 2.1.0
Instance details Defined in Text.Mustache.Type Methods lift :: Quote m => Key -> m Exp # liftTyped :: forall (m :: Type -> Type). Quote m => Key -> Code m Key #
type Rep Key # |
Instance details Defined in Text.Mustache.Type type Rep Key = D1 ('MetaData "Key" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "Key" 'PrefixI 'True) (S1 ('MetaSel ('Just "unKey") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 [Text])))

newtype PName #

Identifier for partials. Note that with the `OverloadedStrings` extension you can use just string literals to create values of this type.

Constructors

PName |
Fields unPName :: Text

#### Instances

Instances details

NFData PName # |
Instance details Defined in Text.Mustache.Type Methods rnf :: PName -> () #
Data PName # |
Instance details Defined in Text.Mustache.Type Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> PName -> c PName # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c PName # toConstr :: PName -> Constr # dataTypeOf :: PName -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c PName) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c PName) # gmapT :: (forall b. Data b => b -> b) -> PName -> PName # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> PName -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> PName -> r # gmapQ :: (forall d. Data d => d -> u) -> PName -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> PName -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> PName -> m PName # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> PName -> m PName # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> PName -> m PName #
IsString PName # |
Instance details Defined in Text.Mustache.Type Methods fromString :: String -> PName #
Generic PName # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep PName |
Instance details Defined in Text.Mustache.Type type Rep PName = D1 ('MetaData "PName" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "PName" 'PrefixI 'True) (S1 ('MetaSel ('Just "unPName") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)))
Methods from :: PName -> Rep PName x # to :: Rep PName x -> PName #
Show PName # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> PName -> ShowS # show :: PName -> String # showList :: [PName] -> ShowS #
Eq PName # |
Instance details Defined in Text.Mustache.Type Methods (==) :: PName -> PName -> Bool # (/=) :: PName -> PName -> Bool #
Ord PName # |
Instance details Defined in Text.Mustache.Type Methods compare :: PName -> PName -> Ordering # (<) :: PName -> PName -> Bool # (<=) :: PName -> PName -> Bool # (>) :: PName -> PName -> Bool # (>=) :: PName -> PName -> Bool # max :: PName -> PName -> PName # min :: PName -> PName -> PName #
Lift PName # | Since: 2.1.0
Instance details Defined in Text.Mustache.Type Methods lift :: Quote m => PName -> m Exp # liftTyped :: forall (m :: Type -> Type). Quote m => PName -> Code m PName #
type Rep PName # |
Instance details Defined in Text.Mustache.Type type Rep PName = D1 ('MetaData "PName" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "PName" 'PrefixI 'True) (S1 ('MetaSel ('Just "unPName") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)))

newtype MustacheException #

Exception that is thrown when parsing of a template fails or referenced values are not provided.

Constructors

MustacheParserException (ParseErrorBundle Text Void) | Template parser has failed. This contains the parse error. Before version 0.2.0 it was called `MustacheException`. The `Text` field was added in version 1.0.0.

#### Instances

Instances details

Exception MustacheException # |
Instance details Defined in Text.Mustache.Type Methods toException :: MustacheException -> SomeException # fromException :: SomeException -> Maybe MustacheException # displayException :: MustacheException -> String # backtraceDesired :: MustacheException -> Bool #
Generic MustacheException # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep MustacheException |
Instance details Defined in Text.Mustache.Type type Rep MustacheException = D1 ('MetaData "MustacheException" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "MustacheParserException" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (ParseErrorBundle Text Void))))
Methods from :: MustacheException -> Rep MustacheException x # to :: Rep MustacheException x -> MustacheException #
Show MustacheException # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> MustacheException -> ShowS # show :: MustacheException -> String # showList :: [MustacheException] -> ShowS #
Eq MustacheException # |
Instance details Defined in Text.Mustache.Type Methods (==) :: MustacheException -> MustacheException -> Bool # (/=) :: MustacheException -> MustacheException -> Bool #
type Rep MustacheException # |
Instance details Defined in Text.Mustache.Type type Rep MustacheException = D1 ('MetaData "MustacheException" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'True) (C1 ('MetaCons "MustacheParserException" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (ParseErrorBundle Text Void))))

data MustacheWarning #

Warning that may be generated during rendering of a `Template`.

Since: 1.1.1

Constructors

MustacheVariableNotFound Key | The template contained a variable for which there was no data in the current context.
MustacheDirectlyRenderedValue Key | A complex value such as an `Object` or `Array` was directly rendered into the template.

#### Instances

Instances details

Generic MustacheWarning # |
Instance details Defined in Text.Mustache.Type Associated Types
type Rep MustacheWarning |
Instance details Defined in Text.Mustache.Type type Rep MustacheWarning = D1 ('MetaData "MustacheWarning" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) (C1 ('MetaCons "MustacheVariableNotFound" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)) :+: C1 ('MetaCons "MustacheDirectlyRenderedValue" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)))
Methods from :: MustacheWarning -> Rep MustacheWarning x # to :: Rep MustacheWarning x -> MustacheWarning #
Show MustacheWarning # |
Instance details Defined in Text.Mustache.Type Methods showsPrec :: Int -> MustacheWarning -> ShowS # show :: MustacheWarning -> String # showList :: [MustacheWarning] -> ShowS #
Eq MustacheWarning # |
Instance details Defined in Text.Mustache.Type Methods (==) :: MustacheWarning -> MustacheWarning -> Bool # (/=) :: MustacheWarning -> MustacheWarning -> Bool #
type Rep MustacheWarning # |
Instance details Defined in Text.Mustache.Type type Rep MustacheWarning = D1 ('MetaData "MustacheWarning" "Text.Mustache.Type" "stache-2.3.4-12n8t6Z2eXACjf6tDo3vkh" 'False) (C1 ('MetaCons "MustacheVariableNotFound" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)) :+: C1 ('MetaCons "MustacheDirectlyRenderedValue" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Key)))

displayMustacheWarning :: MustacheWarning -> String #

Pretty-print a `MustacheWarning`.

Since: 1.1.1

# Compiling

compileMustacheDir #

Arguments

:: MonadIO m |
=> PName | Which template to select after compiling
-> FilePath | Directory with templates
-> m Template | The resulting template

Compile all templates in the specified directory and select one. Template files should have the extension `mustache`, (e.g. `foo.mustache`) to be recognized. This function does not scan the directory recursively.

Note that each template/partial will get an identifier which consists of the name of corresponding template file with extension `.mustache` dropped. This is important for e.g. selecting active template after loading (the first argument).

The action can throw `MustacheParserException` and the same exceptions as `getDirectoryContents`, and `readFile`.

    compileMustacheDir = complieMustacheDir' isMustacheFile

compileMustacheDir' #

Arguments

:: MonadIO m |
=> (FilePath -> Bool) | Template selection predicate
-> PName | Which template to select after compiling
-> FilePath | Directory with templates
-> m Template | The resulting template

The same as `compileMustacheDir`, but allows using a custom predicate for template selection.

Since: 1.2.0

compileMustacheFile #

Arguments

:: MonadIO m |
=> FilePath | Location of the file
-> m Template |

Compile a Mustache template and select it.

The action can throw `MustacheParserException` and the same exceptions as `readFile`.

compileMustacheText #

Arguments

:: PName | How to name the template?
-> Text | The template to compile
-> Either (ParseErrorBundle Text Void) Template | The result

Compile a Mustache template from a `Text` value. The cache will contain only this template named according to given `PName`.

# Rendering

renderMustache :: Template -> Value -> Text #

Render a Mustache `Template` using Aeson's `Value` to get actual values for interpolation.

renderMustacheW :: Template -> Value -> ([MustacheWarning], Text) #

Like `renderMustache`, but also returns a collection of warnings.

Since: 1.1.1