Hedi-0.1.1: Line oriented editor Source code Contents Index

Engine

Description

A zipped list with special cursor at the ends. In fact it handles inserting at start and appending at end where the cursor is pointing to non existing lines.

Synopsis

type Change a = a -> Maybe a data Pos = Line { nth :: Int } | Begin | End { lns :: Int } data Engine = Inside { left :: [String] cursor :: String right :: [String] } | Corner { elems :: Either [String] [String] } empty :: Engine listIn :: [String] -> Engine listOut :: Engine -> Maybe [String] linen :: Int -> Engine -> Maybe [String] line :: Engine -> Maybe String jump :: Int -> Change Engine ins :: [String] -> Change Engine add :: [String] -> Change Engine del :: Change Engine deln :: Int -> Change Engine end :: Change Engine start :: Change Engine pos :: Engine -> Pos next :: Change Engine prev :: Change Engine prevn :: Int -> Change Engine nextn :: Int -> Change Engine rjump :: Int -> Change Engine tillend :: Engine -> [Engine] fwdcycle :: Engine -> [Engine] fromstart :: Engine -> [Engine] bwdcycle :: Engine -> [Engine] last :: Change Engine first :: Change Engine isInside :: Engine -> Bool runner :: Change Engine -> Engine -> [Engine]

Documentation

type Change a = a -> Maybe a Source

represent an action, which can fail with Nothing , an index error

data Pos Source

Pos represent the position addressed in the engine Constructors Line the engine addresses a real line nth :: Int The index of the line starting from 1 Begin the engine addresses before first line , if ever present End the engine addresses after last line lns :: Int The number of lines in the engine Instances Show Pos

data Engine Source

relative distance between two positions Constructors Inside the cursor when its pointing to a real line (eg line function doesn't fail) left :: [String] lines before the cursor (reversed order) cursor :: String addressed line right :: [String] lines after the cursor Corner the cursor is pointing either to insert at the front of the file or append at the end of the file. elems :: Either [String] [String] Left lines is in append mode, Right is in insert at front mode. Instances Eq Engine Show Engine

empty :: Engine Source

An empty engine

listIn :: [String] -> Engine Source

An engine is isomorphic to Engine list

listOut :: Engine -> Maybe [String] Source

Extract the list from the engine

linen :: Int -> Engine -> Maybe [String] Source

Extract n lines from the position addressed

line :: Engine -> Maybe String Source

Extract the addressed line

jump :: Int -> Change Engine Source

Possibly set the addressed line to the nth line

ins :: [String] -> Change Engine Source

Insert some lines before the addressed line

add :: [String] -> Change Engine Source

Insert some lines after the addressed line

del :: Change Engine Source

Delete the addressed line , address the next one

deln :: Int -> Change Engine Source

Delete n lines from the addressed position

end :: Change Engine Source

Address an append position

start :: Change Engine Source

Address before the first line

pos :: Engine -> Pos Source

The number of the addressed line

next :: Change Engine Source

Address the next line

prev :: Change Engine Source

Address the prev line

prevn :: Int -> Change Engine Source

Jump back n lines

nextn :: Int -> Change Engine Source

Jump ahead n lines

rjump :: Int -> Change Engine Source

Jump n lines relative to the addredded line

tillend :: Engine -> [Engine] Source

Create all the engines from the addressed one to the last one

fwdcycle :: Engine -> [Engine] Source

all the next engines from the addressed next to itself , wrapping around

fromstart :: Engine -> [Engine] Source

Create all the engines from the start to the addressed one included

bwdcycle :: Engine -> [Engine] Source

all the prev engines from the addressed prev to itself , wrapping around

last :: Change Engine Source

last element if present

first :: Change Engine Source

first element if present

isInside :: Engine -> Bool Source

runner :: Change Engine -> Engine -> [Engine] Source

Produced by Haddock version 2.3.0