Text.Parser.Input.Position

A parser's position in the input.

Documentation

class Ord p => Position p where

A class for representing position values. The methods satisfy these laws:

move (distance pos1 pos2) pos1 == pos2
(pos1 < pos2) == (distance pos1 pos2 > 0)

Methods

distance :: p -> p -> Int

Distance from the first position to the second

move :: Int -> p -> p

Move the position by the given distance.

offset :: FactorialMonoid s => s -> p -> Int

Map the position into its offset from the beginning of the full input.

Instances

Position Int

Defined in Text.Parser.Input.Position

Methods

distance :: Int -> Int -> Int

move :: Int -> Int -> Int

offset :: FactorialMonoid s => s -> Int -> Int

Position a => Position (Down a)

Defined in Text.Parser.Input.Position

Methods

distance :: Down a -> Down a -> Int

move :: Int -> Down a -> Down a

offset :: FactorialMonoid s => s -> Down a -> Int

fromStart :: Int -> Int

Construct a Position given the offset from the beginning of the full input.

fromEnd :: Int -> Down Int

Construct a Position given the length remaining from the position to the end of the input.

context :: (Eq s, TextualMonoid s, Position p) => s -> p -> Int -> s

Given the parser input, a Position within it, and desired number of context lines, returns a description of the offset position in English.

lineAndColumn :: (Eq s, IsString s, FactorialMonoid s, Position p) => s -> p -> ([s], Int)

Given the full input and an offset within it, returns all the input lines up to and including the offset in reverse order, as well as the zero-based column number of the offset