Safe Haskell	None
Language	Haskell2010

Data.Text.Offset

Contents

Creation
Querying

Description

Helpers for calculating char/byte offset from line and column number. All line and column offsets in this module are zero-based.

Note: currently only line/column to byte offset calculation is exposed, but the OffsetTable structure supports more, which can be added on demand.

Synopsis

data OffsetTable
createOffsetTable :: Text -> OffsetTable
lineColToByteOffsetDetail :: OffsetTable -> Int -> Int -> Either OffsetError Int
lineColToByteOffset :: OffsetTable -> Int -> Int -> Maybe Int
data OffsetError
- = NoSuchLine
- | EmptyLine
- | OverLineEnd !ByteOffset !OverLineKind
data OverLineKind
- = JustAtLineEnd
- | AfterLineEnd

Documentation

data OffsetTable Source #

Stores info for mapping line/column number (Char-based) to raw offset (either Char or UTF-8 encoded bytes-based).

Instances

Eq OffsetTable Source #
Instance details Defined in Data.Text.Offset Methods (==) :: OffsetTable -> OffsetTable -> Bool # (/=) :: OffsetTable -> OffsetTable -> Bool #
Show OffsetTable Source #
Instance details Defined in Data.Text.Offset Methods showsPrec :: Int -> OffsetTable -> ShowS # show :: OffsetTable -> String # showList :: [OffsetTable] -> ShowS #

Creation

createOffsetTable :: Text -> OffsetTable Source #

Calculates the OffsetTable for the given text. The table calculation is not optimized (non-strict tuples are lying around), but lookups on the result are performant (since the tuples are stored as unboxed vectors).

Querying

lineColToByteOffsetDetail :: OffsetTable -> Int -> Int -> Either OffsetError Int Source #

Line and col are zero-based, col is in characters.

lineColToByteOffset :: OffsetTable -> Int -> Int -> Maybe Int Source #

Like lineColToByteOffsetDetail, but without failure details.

data OffsetError Source #

Constructors

NoSuchLine
EmptyLine
OverLineEnd !ByteOffset !OverLineKind	Clients might want to recover from this case, see `JustAtLineEnd`.

Instances

Eq OffsetError Source #
Instance details Defined in Data.Text.Offset Methods (==) :: OffsetError -> OffsetError -> Bool # (/=) :: OffsetError -> OffsetError -> Bool #
Ord OffsetError Source #
Instance details Defined in Data.Text.Offset Methods compare :: OffsetError -> OffsetError -> Ordering # (<) :: OffsetError -> OffsetError -> Bool # (<=) :: OffsetError -> OffsetError -> Bool # (>) :: OffsetError -> OffsetError -> Bool # (>=) :: OffsetError -> OffsetError -> Bool # max :: OffsetError -> OffsetError -> OffsetError # min :: OffsetError -> OffsetError -> OffsetError #
Show OffsetError Source #
Instance details Defined in Data.Text.Offset Methods showsPrec :: Int -> OffsetError -> ShowS # show :: OffsetError -> String # showList :: [OffsetError] -> ShowS #

data OverLineKind Source #

Constructors

JustAtLineEnd	Referenced position is just after the line content. Position can be a valid non-inclusive ending span offset.
AfterLineEnd

Instances

Eq OverLineKind Source #
Instance details Defined in Data.Text.Offset Methods (==) :: OverLineKind -> OverLineKind -> Bool # (/=) :: OverLineKind -> OverLineKind -> Bool #
Ord OverLineKind Source #
Instance details Defined in Data.Text.Offset Methods compare :: OverLineKind -> OverLineKind -> Ordering # (<) :: OverLineKind -> OverLineKind -> Bool # (<=) :: OverLineKind -> OverLineKind -> Bool # (>) :: OverLineKind -> OverLineKind -> Bool # (>=) :: OverLineKind -> OverLineKind -> Bool # max :: OverLineKind -> OverLineKind -> OverLineKind # min :: OverLineKind -> OverLineKind -> OverLineKind #
Show OverLineKind Source #
Instance details Defined in Data.Text.Offset Methods showsPrec :: Int -> OverLineKind -> ShowS # show :: OverLineKind -> String # showList :: [OverLineKind] -> ShowS #