Pencil.Internal.Parser

Documentation

>>> :set -XOverloadedStrings
>>> import Data.Either (isLeft)

data PNode

Pencil's Page AST.

Constructors

PText Text

PVar Text

PFor Text [PNode]

PIf Text [PNode]

PPartial Text

PPreamble Text

PMetaIf Text

PMetaFor Text

PMetaEnd

Instances

Eq PNode

Methods

(==) :: PNode -> PNode -> Bool

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

Show PNode

Methods

showsPrec :: Int -> PNode -> ShowS

show :: PNode -> String

showList :: [PNode] -> ShowS

data Token

Pencil's tokens for content.

Constructors

TokText Text

TokVar Text

TokFor Text

TokIf Text

TokPartial Text

TokPreamble Text

TokEnd

Instances

Eq Token

Methods

(==) :: Token -> Token -> Bool

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

Show Token

Methods

showsPrec :: Int -> Token -> ShowS

show :: Token -> String

showList :: [Token] -> ShowS

transform :: [Token] -> [PNode]

Convert Tokens to PNode AST.

ast :: [PNode] -> [Token] -> [PNode]

Converts Tokens, which is just the raw list of parsed tokens, into PNodes which are the tree-structure expressions (i.e. if/for nesting)

This function works by using a stack to keep track of where we are for nested expressions such as if and for statements. When a token that starts a nesting is found (like a TokIf), a "meta" expression (PMetaIf) is pushed into the stack. When we finally see an end token (TokEnd), we pop all the expressions off the stack until the first meta tag (e.g PMetaIf) is reached. All the expressions popped off are now known to be nested inside that if statement.

popNodes :: [PNode] -> (PNode, [PNode], [PNode])

Pop nodes until we hit a If/For statement. Return pair (constructor found, nodes popped, remaining stack)

popNodes_ :: [PNode] -> [PNode] -> (PNode, [PNode], [PNode])

Helper for popNodes.

renderNodes :: [PNode] -> Text

Render nodes as string.

renderNode :: PNode -> Text

Render node as string.

renderTokens :: [Token] -> Text

Render tokens.

renderToken :: Token -> Text

Render token.

parseText :: Text -> Either ParseError [PNode]

Parse text.

parseEverything :: Parser [Token]

Parse everything.

parseVar :: Parser Token

Parse variables.

parsePreamble :: Parser Token

Parse preamble.

parsePreambleStart :: Parser String

Parse the start of a PREAMBLE.

parsePartial :: Parser Token

Parse partial commands.

parseContent :: Parser Token

Parse boring, boring text.

parseFor :: Parser Token

Parse for loop declaration.

parseIf :: Parser Token

Parse if directive.

parseFunction :: String -> (Text -> Token) -> Parser Token

General parse template functions.

parseEnd :: Parser Token

Parse end keyword.

parseFakeVar :: Parser Token

A hack to capture strings that "almost" are templates. I couldn't figure out another way.

many1Till :: Stream s m t => ParsecT s u m a -> ParsecT s u m end -> ParsecT s u m [a]

many1Till p end will parse one or more p until @end.

From https://hackage.haskell.org/package/pandoc-1.10.0.4/docs/Text-Pandoc-Parsing.html

findPreambleText :: [PNode] -> Maybe Text

Find the preamble content from the given PNodes.

isPreamble :: PNode -> Bool

Returns True if the PNode is a PPreamble.

preambleText :: PNode -> Maybe Text

Gets the content of the PPreamble