prettyprinter-1.7.0: A modern, easy to use, well-documented, extensible pretty-printer.

Safe HaskellSafe
LanguageHaskell2010

Prettyprinter.Internal.Debug

Description

Warning: internal module! This means that the API may change arbitrarily between versions without notice. Depending on this module may lead to unexpected breakages, so proceed with caution!

This module provides debugging helpers for inspecting Docs.

Use the pretty-simple package to get a nicer layout for shown Diags:

> Text.Pretty.Simple.pPrintNoColor . diag $ align (vcat ["foo", "bar"])
Column
   [
       ( 10
       , Nesting
           [
               ( 10
               , Cat ( Text 3 "foo" )
                   ( Cat ( FlatAlt Line Empty ) ( Text 3 "bar" ) )
               )
           ]
       )
   ]
Synopsis

Documentation

data Diag ann Source #

A variant of Doc for debugging.

Unlike in the Doc type, the Column, WithPageWidth and Nesting constructors don't contain functions but are "sampled" to allow simple inspection with show.

Constructors

Fail 
Empty 
Char !Char 
Text !Int !Text 
Line 
FlatAlt (Diag ann) (Diag ann) 
Cat (Diag ann) (Diag ann) 
Nest !Int (Diag ann) 
Union (Diag ann) (Diag ann) 
Column [(Int, Diag ann)]

Doc: (Int -> Diag ann)

WithPageWidth [(PageWidth, Diag ann)]

Doc: (PageWidth -> Diag ann)

Nesting [(Int, Diag ann)]

Doc: (Int -> Diag ann)

Annotated ann (Diag ann) 
Instances
Show ann => Show (Diag ann) Source # 
Instance details

Defined in Prettyprinter.Internal.Debug

Methods

showsPrec :: Int -> Diag ann -> ShowS #

show :: Diag ann -> String #

showList :: [Diag ann] -> ShowS #

diag :: Doc ann -> Diag ann Source #

Convert a Doc to its diagnostic representation.

The functions in the Column, WithPageWidth and Nesting constructors are sampled with some default values.

Use diag' to control the function inputs yourself.

>>> diag $ Doc.align (Doc.vcat ["foo", "bar"])
Column [(10,Nesting [(10,Cat (Text 3 "foo") (Cat (FlatAlt Line Empty) (Text 3 "bar")))])]

diag' Source #

Arguments

:: [Int]

Cursor positions for the Column constructor

-> [PageWidth]

For WithPageWidth

-> [Int]

Nesting levels for Nesting

-> Doc ann 
-> Diag ann