diff --git a/changelog.md b/changelog.md --- a/changelog.md +++ b/changelog.md @@ -1,5 +1,26 @@ # doctemplates +## 0.8.3 + + * Properly handle nested loops (#15). Previously "it" was + always used for the variable in a loop, and in a nested loop + there was no way to distinguish the value of the inner + iteration from the value of the outer one. Now we assign + the iterated value to both "it" and to the original variable + name (e.g. "foo.bar"). This probably has a small negative + performance impact. Note that this change also affects + the output of the template parser: original variable + names are now retained instead of being replaced by "it". + + * Remove duplicate IsString constraint (#14, Mario Lang). + + * Update haddocks from README (#10). + + * Minor code clean-ups (#7, favonia). + + * Add hsyaml >= 0.2 constraint (#6). + + ## 0.8.2 * Add filters: first, rest, last, allbutlast. diff --git a/doctemplates.cabal b/doctemplates.cabal --- a/doctemplates.cabal +++ b/doctemplates.cabal @@ -1,5 +1,5 @@ name: doctemplates -version: 0.8.2 +version: 0.8.3 synopsis: Pandoc-style document templates description: This is the text templating system used by pandoc. It supports variable interpolation, iteration, @@ -32,7 +32,7 @@ safe, text-conversions, aeson, - HsYAML, + HsYAML >= 0.2 && < 0.3, text, doclayout >= 0.3 && < 0.4, containers, diff --git a/src/Text/DocTemplates.hs b/src/Text/DocTemplates.hs --- a/src/Text/DocTemplates.hs +++ b/src/Text/DocTemplates.hs @@ -14,9 +14,9 @@ Control structures are provided to test whether a variable has a non-blank value and to iterate over the items of a list. Partials—that -is, subtemplates defined in different files—are supported. Filters can -be used to transform the values of variables or partials. The provided -filters make it possible to do list enumeration and tabular layout in +is, subtemplates defined in different files—are supported. Pipes can be +used to transform the values of variables or partials. The provided +pipes make it possible to do list enumeration and tabular layout in templates. Templates are rendered to a doclayout @Doc@ (which is polymorphic in the @@ -309,11 +309,11 @@ The @~@ keyword has no effect when rendering to @Text@ or @String@. -== Filters +== Pipes -A filter transforms the value of a variable or partial. Filters are +A pipe transforms the value of a variable or partial. Pipes are specified using a slash (@\/@) between the variable name (or partial) -and the filter name. Example: +and the pipe name. Example: > $for(name)$ > $name/uppercase$ @@ -325,13 +325,13 @@ > > $employee:name()/uppercase$ -Filters may be chained: +Pipes may be chained: > $for(employees/pairs)$ > $it.key/alpha/uppercase$. $it.name$ > $endfor$ -Some filters take parameters: +Some pipes take parameters: > |----------------------|------------| > $for(employee)$ @@ -339,11 +339,23 @@ > $endfor$ > |----------------------|------------| -Currently the following filters are predefined: +Currently the following pipes are predefined: - @pairs@: Converts a map or array to an array of maps, each with @key@ and @value@ fields. If the original value was an array, the @key@ will be the array index, starting with 1. + +- @first@: Returns the first value of an array, if applied to a + non-empty array; otherwise returns the original value. + +- @last@: Returns the last value of an array, if applied to a + non-empty array; otherwise returns the original value. + +- @rest@: Returns all but the first value of an array, if applied to a + non-empty array; otherwise returns the original value. + +- @allbutlast@: Returns all but the last value of an array, if applied + to a non-empty array; otherwise returns the original value. - @uppercase@: Converts text to uppercase. diff --git a/src/Text/DocTemplates/Internal.hs b/src/Text/DocTemplates/Internal.hs --- a/src/Text/DocTemplates/Internal.hs +++ b/src/Text/DocTemplates/Internal.hs @@ -2,7 +2,6 @@ {-# LANGUAGE ConstraintKinds #-} {-# LANGUAGE GeneralizedNewtypeDeriving #-} {-# LANGUAGE MultiParamTypeClasses #-} -{-# LANGUAGE TypeSynonymInstances #-} {-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE FlexibleInstances #-} {-# LANGUAGE OverloadedStrings #-} @@ -10,8 +9,6 @@ {-# LANGUAGE DeriveDataTypeable #-} {-# LANGUAGE DeriveGeneric #-} {-# LANGUAGE DeriveTraversable #-} -{-# LANGUAGE DeriveFoldable #-} -{-# LANGUAGE DeriveFunctor #-} {- | Module : Text.DocTemplates.Internal @@ -44,6 +41,7 @@ import Control.Monad.Identity import qualified Control.Monad.State.Strict as S import Data.Char (chr, ord) +import Data.Maybe (fromMaybe) import qualified Data.Text.Read as T import qualified Data.Text as T import qualified Data.Text.IO as TIO @@ -166,15 +164,15 @@ toVal = SimpleVal . DL.literal instance ToContext a a => ToContext a (Doc a) where - toVal = SimpleVal + toVal = SimpleVal -- This is needed because otherwise the compiler tries to -- match on ToContext a [b], with a = b = Char, even though -- we don't have ToContext Char Char. I don't understand why. -instance {-# OVERLAPS #-} ToContext String String where +instance {-# OVERLAPPING #-} ToContext String String where toVal = SimpleVal . DL.literal -instance {-# OVERLAPS #-} ToContext String (Doc String) where +instance {-# OVERLAPPING #-} ToContext String (Doc String) where toVal = SimpleVal instance ToContext a b => ToContext a [b] where @@ -188,7 +186,7 @@ toVal True = SimpleVal "true" toVal False = NullVal -instance (IsString a, TemplateTarget a) => ToContext a Value where +instance TemplateTarget a => ToContext a Value where toContext x = case fromJSON x of Success y -> y Error _ -> mempty @@ -217,7 +215,7 @@ -- This is needed because otherwise the compiler tries to -- match on FromContext a [b], with a = b = Char, even though -- we don't have FromContext Char Char. I don't understand why. -instance {-# OVERLAPS #-} FromContext String String where +instance {-# OVERLAPPING #-} FromContext String String where fromVal (SimpleVal x) = Just (DL.render Nothing x) fromVal _ = Nothing @@ -225,7 +223,7 @@ fromVal (ListVal xs) = mapM fromVal xs fromVal x = sequence [fromVal x] -instance (IsString a, TemplateTarget a) => FromJSON (Val a) where +instance TemplateTarget a => FromJSON (Val a) where parseJSON v = case v of Array vec -> ListVal <$> mapM parseJSON (V.toList vec) @@ -239,7 +237,7 @@ mapM parseJSON o _ -> return NullVal -instance (IsString a, TemplateTarget a) => FromJSON (Context a) where +instance TemplateTarget a => FromJSON (Context a) where parseJSON v = do val <- parseJSON v case val of @@ -261,7 +259,7 @@ Scalar _ (SBool True) -> return $ SimpleVal "true" _ -> return NullVal -instance (IsString a, TemplateTarget a) => FromYAML (Context a) where +instance TemplateTarget a => FromYAML (Context a) where parseYAML v = do val <- parseYAML v case val of @@ -349,7 +347,7 @@ applyPipe ToRoman val = mapText toRoman' val where toRoman' t = case T.decimal t of - Right (y,"") -> maybe t id (toRoman y) + Right (y,"") -> fromMaybe t (toRoman y) _ -> t applyPipe NoWrap val = mapDoc DL.nowrap val applyPipe (Block align n border) val = @@ -424,14 +422,23 @@ withVariable :: (Monad m, TemplateTarget a) => Variable -> Context a -> (Context a -> m (Doc a)) -> m [Doc a] -withVariable v ctx f = - case applyPipes (varPipes v) $ multiLookup (varParts v) (MapVal ctx) of +withVariable var ctx f = + case applyPipes (varPipes var) $ multiLookup (varParts var) (MapVal ctx) of NullVal -> return mempty - ListVal xs -> mapM (\iterval -> f $ - Context $ M.insert "it" iterval $ unContext ctx) xs - MapVal ctx' -> (:[]) <$> f - (Context $ M.insert "it" (MapVal ctx') $ unContext ctx) - val' -> (:[]) <$> f (Context $ M.insert "it" val' $ unContext ctx) + ListVal xs -> mapM (\iterval -> f $ setVarVal iterval) xs + MapVal ctx' -> (:[]) <$> f (setVarVal (MapVal ctx')) + val' -> (:[]) <$> f (setVarVal val') + where + setVarVal x = + addToContext var x $ Context $ M.insert "it" x $ unContext ctx + addToContext (Variable [] _) _ (Context ctx') = Context ctx' + addToContext (Variable (v:vs) fs) x (Context ctx') = + Context $ M.adjust + (\z -> case z of + _ | null vs -> x + MapVal m -> + MapVal $ addToContext (Variable vs fs) x m + _ -> z) v ctx' type RenderState = S.State Int @@ -448,7 +455,7 @@ renderTemp :: forall a . TemplateTarget a => Template a -> Context a -> RenderState (Doc a) -renderTemp (Literal t) _ = updateColumn $ t +renderTemp (Literal t) _ = updateColumn t renderTemp (Interpolate v) ctx = updateColumn $ mconcat $ resolveVariable v ctx renderTemp (Conditional v ift elset) ctx = let res = resolveVariable v ctx diff --git a/src/Text/DocTemplates/Parser.hs b/src/Text/DocTemplates/Parser.hs --- a/src/Text/DocTemplates/Parser.hs +++ b/src/Text/DocTemplates/Parser.hs @@ -1,6 +1,5 @@ {-# LANGUAGE CPP #-} {-# LANGUAGE OverloadedStrings #-} -{-# LANGUAGE BangPatterns #-} {- | Module : Text.DocTemplates.Parser Copyright : Copyright (C) 2009-2019 John MacFarlane @@ -24,7 +23,6 @@ import Data.Text (Text) import qualified Data.Text as T import qualified Data.Text.Read as T -import Data.List (isPrefixOf) import System.FilePath import Text.DocTemplates.Internal import qualified Text.DocLayout as DL @@ -140,10 +138,9 @@ pDirective :: (TemplateTarget a, TemplateMonad m) => Parser m (Template a) -pDirective = do - res <- pConditional <|> pForLoop <|> pReflowToggle <|> pNested <|> - pInterpolate <|> pBarePartial - return res +pDirective = + pConditional <|> pForLoop <|> pReflowToggle <|> pNested <|> + pInterpolate <|> pBarePartial pEnclosed :: Monad m => Parser m a -> Parser m a pEnclosed parser = P.try $ do @@ -227,7 +224,7 @@ return (y <> z) let contents = x <> mconcat xs P.updateState $ \st -> st{ nestedCol = oldNested } - return $ Nested $ contents + return $ Nested contents pForLoop :: (TemplateTarget a, TemplateMonad m) => Parser m (Template a) pForLoop = do @@ -235,31 +232,14 @@ -- if newline after the "for", then a newline after "endfor" will be swallowed pInside $ do multiline <- P.option False $ skipEndline >> return True - contents <- changeToIt v <$> pTemplate + contents <- pTemplate sep <- P.option mempty $ do pEnclosed (P.string "sep") when multiline $ P.option () skipEndline - changeToIt v <$> pTemplate + pTemplate pEnclosed (P.string "endfor") when multiline $ P.option () skipEndline return $ Iterate v contents sep - -changeToIt :: (Semigroup a) => Variable -> Template a -> Template a -changeToIt v = go - where - go (Interpolate w) = Interpolate (reletter v w) - go (Conditional w t1 t2) = Conditional (reletter v w) - (changeToIt v t1) (changeToIt v t2) - go (Iterate w t1 t2) = Iterate (reletter v w) - (changeToIt v t1) (changeToIt v t2) - go (Concat t1 t2) = changeToIt v t1 <> changeToIt v t2 - go (Partial fs t) = Partial fs t -- don't reletter inside partial - go (Nested t) = Nested (go t) - go x = x - reletter (Variable vs _fs) (Variable ws gs) = - if vs `isPrefixOf` ws - then Variable ("it" : drop (length vs) ws) gs - else Variable ws gs pInterpolate :: (TemplateTarget a, TemplateMonad m) => Parser m (Template a) diff --git a/test/nested-loop.test b/test/nested-loop.test new file mode 100644 --- /dev/null +++ b/test/nested-loop.test @@ -0,0 +1,41 @@ +{ + "pages": [ + { + "subpages": [ + { + "slug": "subpage-1" + }, + { + "slug": "subpage-2" + } + ], + "slug": "page-1" + }, + { + "subpages": [ + { + "slug": "subpage-1" + }, + { + "slug": "subpage-2" + } + ], + "slug": "page-2" + } + ] +} +. +$-- see #15 +$for(pages)$ +/$pages.slug$ +$for(pages.subpages)$ + /$pages.slug$/$pages.subpages.slug$ +$endfor$ +$endfor$ +. +/page-1 + /page-1/subpage-1 + /page-1/subpage-2 +/page-2 + /page-2/subpage-1 + /page-2/subpage-2