Portability	to be determined.
Stability	highly unstable
Maintainer	Stephen Tetley <stephen.tetley@gmail.com>

Text.PrettyPrint.JoinPrint

Contents

Compose Docs
Compose VDocs
Primitive Docs
Padding and truncation
Output

Description

Printing with join-strings.

Note - JoinPrint is just a formatter and not a 'pretty printer'. No line fitting takes place - lines are printed exactly as they are specified.

Synopsis

Documentation

data Doc Source

Doc is the abstract data type respresenting single line documents.

JoinPrint ditinguishes between single-line and multi-line documents. Single-line, horizontal documents support some operations not multi-line documents, e.g. padding, see padl and padr and truncating truncl and truncr.

Instances

Show Doc
Monoid Doc

data VDoc Source

VDoc is the abstract data type respresenting multi-line documents.

Multi-line documents have a limited set of operations (basically concatenation with or without a blank line inbetween) compared to single line docs which support e.g. padding and truncating.

Instances

Show VDoc
Monoid VDoc

empty :: Doc Source

Create an empty, zero length document.

null :: Doc -> Bool Source

Test if the doc is empty.

length :: Doc -> Int Source

Get the length of the Doc.

Length is cached in the document's data type so this operation is O(1).

Compose Docs

(<>) :: Doc -> Doc -> Doc Source

Horizontally concatenate two documents with no space between them.

(<+>) :: Doc -> Doc -> Doc Source

Horizontally concatenate two documents with a single space between them.

hcat :: [Doc] -> Doc Source

Horizontally concatenate a list of documents with (<>).

hsep :: [Doc] -> Doc Source

Horizontally concatenate a list of documents with (<+>).

Compose VDocs

vcat :: [Doc] -> VDoc Source

Vertically concatenate a list of documents, one doc per line.

Note - this function produces a VDoc rather than a Doc.

vsep :: [Doc] -> VDoc Source

Vertically concatenate a list of documents, one doc per line with a blank line inbetween.

Note - this function produces a VDoc rather than a Doc.

vcons :: Doc -> VDoc -> VDoc Source

Prefix the Doc to the start of the VDoc.

vsnoc :: VDoc -> Doc -> VDoc Source

Suffix the VDoc with the Doc.

vconcat :: [VDoc] -> VDoc Source

Concatenate a list of VDoc.

vconcatSep :: [VDoc] -> VDoc Source

Concatenate a list of VDoc with a blank line separating them.

Primitive Docs

text :: String -> Doc Source

Create a document from a literal string.

The string should not contain tabs or newlines (though this is not enforced). To allow padding and truncating the horizontal width of a Doc is cached in the datatype, building a Doc containing tabs or newlines leads to unspecified behaviour.

char :: Char -> Doc Source

Create a document from a literal character.

The char should not be a tab or newline. See text for the rational.

int :: Int -> Doc Source

Show the Int as a Doc.

 int  = text . show

integer :: Integer -> Doc Source

Show the Integer as a Doc.

integral :: Integral a => a -> Doc Source

Show an "integral value" as a Doc via fromIntegral.

float :: Double -> Doc Source

Show the Float as a Doc.

double :: Double -> Doc Source

Show the Double as a Doc.

sglspace :: Doc Source

Create a Doc containing a single space character.

dblspace :: Doc Source

Create a Doc containing a two-space characters.

comma :: Doc Source

Create a Doc containing a comma, ",".

semicolon :: Doc Source

Create a Doc containing a semi colon, ";".

punctuate :: Doc -> [Doc] -> Doc Source

Punctuate the Doc list with the separator, producing a Doc.

enclose :: Doc -> Doc -> Doc -> Doc Source

Enclose the final Doc within the first two.

There are no spaces between the documents:

 enclose l r d = l <> d <> r

squotes :: Doc -> Doc Source

Enclose the Doc within single quotes.

dquotes :: Doc -> Doc Source

Enclose the Doc within double quotes.

parens :: Doc -> Doc Source

Enclose the Doc within parens ().

brackets :: Doc -> Doc Source

Enclose the Doc within square brackets [].

braces :: Doc -> Doc Source

Enclose the Doc within curly braces {}.

angles :: Doc -> Doc Source

Enclose the Doc within angle brackets <>.

lparen :: Doc Source

Create a Doc containing a left paren, '('.

rparen :: Doc Source

Create a Doc containing a right paren, ')'.

lbracket :: Doc Source

Create a Doc containing a left square bracket, '['.

rbracket :: Doc Source

Create a Doc containing a right square bracket, ']'.

lbrace :: Doc Source

Create a Doc containing a left curly brace, '{'.

rbrace :: Doc Source

Create a Doc containing a right curly brace, '}'.

langle :: Doc Source

Create a Doc containing a left angle bracket, '<'.

rangle :: Doc Source

Create a Doc containing a right angle bracket, '>'.

replicateChar :: Int -> Char -> Doc Source

replicateChar : n * ch -> Doc

Repeat the supplied char (ch), n times.

spacer :: Int -> Doc Source

Create a list of space characters of length n.

Padding and truncation

padl :: Int -> Char -> Doc -> Doc Source

padl : width * ch * doc -> Doc

Pad the supplied Doc to fit width using the char ch. Padding is performed at the left, right-justifying the Doc.

If the doc is already wider than supplied width it is returned as-is (no truncation takes place).

padr :: Int -> Char -> Doc -> Doc Source

padr : width * ch * doc -> Doc

Pad the supplied Doc to fit width using the char ch. Padding is performed at the right, left-justifying the Doc.

If the doc is already wider than supplied width it is returned as-is (no truncation takes place).

truncl :: Int -> Doc -> Doc Source

truncl : width * doc -> Doc

Truncate a doc to the supplied width. Characters are dropped from the left until the document fits. If the document is shorter than the supplied width it is returned as is (no padding takes place).

truncr :: Int -> Doc -> Doc Source

truncr : width * doc -> Doc

Truncate a doc to the supplied width. Characters are dropped from the right until the document fits. If the document is shorter than the supplied width it is returned as is (no padding takes place).