Toml.Pretty

This module provides human-readable renderers for types used in this package to assist error message production.

The generated Doc values are annotated with DocClass values to assist in producing syntax-highlighted outputs.

To extract a plain String representation, use show.

Types

type TomlDoc = Doc DocClass

Pretty-printer document with TOML class attributes to aid in syntax-highlighting.

data DocClass

Annotation used to enable styling pretty-printed TOML

Constructors

TableClass

top-level [key] and [[key]]

KeyClass

dotted keys, left-hand side of assignments

StringClass

string literals

NumberClass

number literals

DateClass

date and time literals

BoolClass

boolean literals

Instances

Read DocClass

Defined in Toml.Pretty

Methods

readsPrec :: Int -> ReadS DocClass

readList :: ReadS [DocClass]

readPrec :: ReadPrec DocClass

readListPrec :: ReadPrec [DocClass]

Show DocClass

Defined in Toml.Pretty

Methods

showsPrec :: Int -> DocClass -> ShowS

show :: DocClass -> String

showList :: [DocClass] -> ShowS

Eq DocClass

Defined in Toml.Pretty

Methods

(==) :: DocClass -> DocClass -> Bool

(/=) :: DocClass -> DocClass -> Bool

Ord DocClass

Defined in Toml.Pretty

Methods

compare :: DocClass -> DocClass -> Ordering

(<) :: DocClass -> DocClass -> Bool

(<=) :: DocClass -> DocClass -> Bool

(>) :: DocClass -> DocClass -> Bool

(>=) :: DocClass -> DocClass -> Bool

max :: DocClass -> DocClass -> DocClass

min :: DocClass -> DocClass -> DocClass

Printing semantic values

prettyToml

Arguments

:: Table

table to print

-> TomlDoc

TOML syntax

Render a complete TOML document using top-level table and array of table sections where possible.

Keys are sorted alphabetically. To provide a custom ordering, see prettyTomlOrdered.

prettyTomlOrdered

Arguments

:: Ord a

=> ([String] -> String -> a)

table path -> key -> projection

-> Table

table to print

-> TomlDoc

TOML syntax

Render a complete TOML document like prettyToml but use a custom key ordering. The comparison function has access to the complete key path. Note that only keys in the same table will every be compared.

This operation allows you to render your TOML files with the most important sections first. A TOML file describing a package might desire to have the [package] section first before any of the ancilliary configuration sections.

The table path is the name of the table being sorted. This allows the projection to be aware of which table is being sorted.

The key is the key in the table being sorted. These are the keys that will be compared to each other.

Here's a projection that puts the package section first, the secondary section second, and then all remaining cases are sorted alphabetically afterward.

example :: [String] -> String -> Either Int String
example [] "package" = Left 1
example [] "second"  = Left 2
example _  other     = Right other

We could also put the tables in reverse-alphabetical order by leveraging an existing newtype.

reverseOrderProj :: [String] -> String -> Down String
reverseOrderProj _ = Down

Since: 1.2.1.0

prettyValue :: Value -> TomlDoc

Render a value suitable for assignment on the right-hand side of an equals sign. This value will always use inline table and list syntax.

Printing syntactic components

prettyToken :: Token -> String

Render token for human-readable error messages.

prettySectionKind :: SectionKind -> NonEmpty String -> TomlDoc

Pretty-print a section heading. The result is annotated as a TableClass.

Printing keys

prettySimpleKey :: String -> Doc a

Renders a simple-key using quotes where necessary.

prettyKey :: NonEmpty String -> TomlDoc

Renders a dotted-key using quotes where necessary and annotated as a KeyClass.

Pretty errors

prettySemanticError :: SemanticError -> String

Render a semantic TOML error in a human-readable string.

Since: 1.3.0.0

prettyMatchMessage :: MatchMessage -> String

Render a TOML decoding error as a human-readable string.

Since: 1.3.0.0

prettyLocated :: Located String -> String