ghc-7.0.1: The GHC API

SrcLoc

Contents

SrcLoc
SrcSpan
Located

Description

This module contains types that relate to the positions of things in source files, and allow tagging of those things with locations

Synopsis

SrcLoc

data SrcLoc Source

Represents a single point within a file

Instances

Eq SrcLoc
Ord SrcLoc
Outputable SrcLoc

Constructing SrcLoc

mkSrcLoc :: FastString -> Int -> Int -> SrcLoc Source

mkGeneralSrcLoc :: FastString -> SrcLoc Source

Creates a bad SrcLoc that has no detailed information about its location

noSrcLoc :: SrcLoc Source

generatedSrcLoc :: SrcLoc Source

Built-in bad SrcLoc values for particular locations

interactiveSrcLoc :: SrcLoc Source

advanceSrcLoc :: SrcLoc -> Char -> SrcLoc Source

Move the SrcLoc down by one line if the character is a newline, to the next 8-char tabstop if it is a tab, and across by one character in any other case

Unsafely deconstructing SrcLoc

srcLocFile :: SrcLoc -> FastString Source

Gives the filename of the SrcLoc if it is available, otherwise returns a dummy value

srcLocLine :: SrcLoc -> Int Source

Raises an error when used on a bad SrcLoc

srcLocCol :: SrcLoc -> Int Source

Raises an error when used on a bad SrcLoc

Misc. operations on SrcLoc

pprDefnLoc :: SrcSpan -> SDoc Source

Pretty prints information about the SrcSpan in the style defined at ...

Predicates on SrcLoc

isGoodSrcLoc :: SrcLoc -> Bool Source

Good SrcLocs have precise information about their location

SrcSpan

data SrcSpan Source

A SrcSpan delimits a portion of a text file. It could be represented by a pair of (line,column) coordinates, but in fact we optimise slightly by using more compact representations for single-line and zero-length spans, both of which are quite common.

The end position is defined to be the column after the end of the span. That is, a span of (1,1)-(1,2) is one character long, and a span of (1,1)-(1,1) is zero characters long.

Instances

Eq SrcSpan
Data SrcSpan
Ord SrcSpan
Typeable SrcSpan
Outputable SrcSpan

Constructing SrcSpan

mkGeneralSrcSpan :: FastString -> SrcSpan Source

Create a bad SrcSpan that has not location information

mkSrcSpan :: SrcLoc -> SrcLoc -> SrcSpan Source

Create a SrcSpan between two points in a file

noSrcSpan :: SrcSpan Source

wiredInSrcSpan :: SrcSpan Source

Built-in bad SrcSpans for common sources of location uncertainty

srcLocSpan :: SrcLoc -> SrcSpan Source

Create a SrcSpan corresponding to a single point

combineSrcSpans :: SrcSpan -> SrcSpan -> SrcSpan Source

Combines two SrcSpan into one that spans at least all the characters within both spans. Assumes the file part is the same in both inputs

Deconstructing SrcSpan

srcSpanStart :: SrcSpan -> SrcLoc Source

Returns the location at the start of the SrcSpan or a bad SrcSpan if that is unavailable

srcSpanEnd :: SrcSpan -> SrcLoc Source

Returns the location at the end of the SrcSpan or a bad SrcSpan if that is unavailable

srcSpanFileName_maybe :: SrcSpan -> Maybe FastString Source

Obtains the filename for a SrcSpan if it is good

Unsafely deconstructing SrcSpan

srcSpanFile :: SrcSpan -> FastString Source

srcSpanStartLine :: SrcSpan -> Int Source

Raises an error when used on a bad SrcSpan

srcSpanEndLine :: SrcSpan -> Int Source

Raises an error when used on a bad SrcSpan

srcSpanStartCol :: SrcSpan -> Int Source

Raises an error when used on a bad SrcSpan

srcSpanEndCol :: SrcSpan -> Int Source

Raises an error when used on a bad SrcSpan

Predicates on SrcSpan

isGoodSrcSpan :: SrcSpan -> Bool Source

Test if a SrcSpan is good, i.e. has precise location information

isOneLineSpan :: SrcSpan -> Bool Source

True if the span is known to straddle only one line. For bad SrcSpan, it returns False

Located

data Located e Source

We attach SrcSpans to lots of things, so let's have a datatype for it.

Constructors

Instances

Functor Located
Typeable1 Located
Eq e => Eq (Located e)
Data e => Data (Located e)
Ord e => Ord (Located e)
Outputable e => Outputable (Located e)

Constructing Located

noLoc :: e -> Located eSource

mkGeneralLocated :: String -> e -> Located eSource

Deconstructing Located

getLoc :: Located e -> SrcSpan Source

unLoc :: Located e -> eSource

Combining and comparing Located values

eqLocated :: Eq a => Located a -> Located a -> Bool Source

Tests whether the two located things are equal

cmpLocated :: Ord a => Located a -> Located a -> Ordering Source

Tests the ordering of the two located things

combineLocs :: Located a -> Located b -> SrcSpan Source

addCLoc :: Located a -> Located b -> c -> Located cSource

Combine locations from two Located things and add them to a third thing

leftmost_smallest :: SrcSpan -> SrcSpan -> Ordering Source

leftmost_largest :: SrcSpan -> SrcSpan -> Ordering Source

Alternative strategies for ordering SrcSpans

rightmost :: SrcSpan -> SrcSpan -> Ordering Source

spans :: SrcSpan -> (Int, Int) -> Bool Source

Determines whether a span encloses a given line and column index

isSubspanOf Source

Arguments

:: SrcSpan	The span that may be enclosed by the other
-> SrcSpan	The span it may be enclosed by
-> Bool

Determines whether a span is enclosed by another one