Erd.ER

Documentation

data ER

Represents a single schema.

Constructors

ER

Fields

• entities :: [Entity]
• rels :: [Relation]
• title :: Options

Instances

Eq ER

Defined in Erd.ER

Methods

(==) :: ER -> ER -> Bool

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

Show ER

Defined in Erd.ER

Methods

showsPrec :: Int -> ER -> ShowS

show :: ER -> String

showList :: [ER] -> ShowS

data Entity

Represents a single entity in a schema.

Constructors

Entity

Fields

• name :: Text
• attribs :: [Attribute]
• hoptions :: Options
• eoptions :: Options

Instances

Eq Entity

Defined in Erd.ER

Methods

(==) :: Entity -> Entity -> Bool

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

Ord Entity

Defined in Erd.ER

Methods

compare :: Entity -> Entity -> Ordering

(<) :: Entity -> Entity -> Bool

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

(>) :: Entity -> Entity -> Bool

(>=) :: Entity -> Entity -> Bool

max :: Entity -> Entity -> Entity

min :: Entity -> Entity -> Entity

Show Entity

Defined in Erd.ER

Methods

showsPrec :: Int -> Entity -> ShowS

show :: Entity -> String

showList :: [Entity] -> ShowS

data Attribute

Represents a single attribute in a particular entity.

Constructors

Attribute

Fields

• field :: Text
• pk :: Bool
• fk :: Bool
• aoptions :: Options

Instances

Eq Attribute

Defined in Erd.ER

Methods

(==) :: Attribute -> Attribute -> Bool

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

Ord Attribute

Defined in Erd.ER

Methods

compare :: Attribute -> Attribute -> Ordering

(<) :: Attribute -> Attribute -> Bool

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

(>) :: Attribute -> Attribute -> Bool

(>=) :: Attribute -> Attribute -> Bool

max :: Attribute -> Attribute -> Attribute

min :: Attribute -> Attribute -> Attribute

Show Attribute

Defined in Erd.ER

Methods

showsPrec :: Int -> Attribute -> ShowS

show :: Attribute -> String

showList :: [Attribute] -> ShowS

type Options = Map String Option

Represents any number of options for an item in an ER diagram. An item may be the graph title, an entity, an entity header or a relationship between entities. Keys are options as specified in ER files.

Note that a set of options may include a label for any item.

mergeOpts :: Options -> Options -> Options

Given two sets of options, merge the second into first, where elements in the first take precedence.

optionsTo :: (Option -> Maybe a) -> Options -> [a]

Given a set of options and a selector function, return the list of only those options which matched. Examples of the selector function are optToFont, optToHtml and optToLabel.

data Option

A restricted subset of options in GraphViz that can be configured in an ER file.

Constructors

Label String

BgColor Color

Color Color

FontFace Text

FontSize Double

Border Word8

BorderColor Color

CellSpacing Word8

CellBorder Word8

CellPadding Word8

TextAlignment Align

Instances

Eq Option

Defined in Erd.ER

Methods

(==) :: Option -> Option -> Bool

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

Show Option

Defined in Erd.ER

Methods

showsPrec :: Int -> Option -> ShowS

show :: Option -> String

showList :: [Option] -> ShowS

optionByName :: String -> String -> Either String Option

Given an option name and a string representation of its value, optionByName will attempt to parse the string as a value corresponding to the option. If the option doesn't exist or there was a problem parsing the value, an error is returned.

optToFont :: Option -> Maybe Attribute

Selects an option if and only if it corresponds to a font attribute.

optToHtml :: Option -> Maybe Attribute

Selects an option if and only if it corresponds to an HTML attribute. In particular, for tables or table cells.

optToLabel :: Option -> Maybe Text

Selects an option if and only if it corresponds to a label.

data Relation

Represents a relationship between exactly two entities. After parsing, each rel is guaranteed to correspond to an entity defined in the same ER file.

Each relationship has one of four cardinalities specified for both entities. Those cardinalities are: 0 or 1, exactly 1, 0 or more and 1 or more.

Constructors

Relation

Fields

• entity1, entity2 :: Text
• card1, card2 :: Cardinality
• roptions :: Options

Instances

Eq Relation

Defined in Erd.ER

Methods

(==) :: Relation -> Relation -> Bool

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

Show Relation

Defined in Erd.ER

Methods

showsPrec :: Int -> Relation -> ShowS

show :: Relation -> String

showList :: [Relation] -> ShowS

data Cardinality

Constructors

ZeroOne

One

ZeroPlus

OnePlus

Instances

Eq Cardinality

Defined in Erd.ER

Methods

(==) :: Cardinality -> Cardinality -> Bool

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

Show Cardinality

Defined in Erd.ER

Methods

showsPrec :: Int -> Cardinality -> ShowS

show :: Cardinality -> String

showList :: [Cardinality] -> ShowS

cardByName :: Char -> Maybe Cardinality

Maps a string representation to a particular relationship cardinality.

defaultAttrOpts :: Options

defaultTitleOpts :: Options

Hard-coded default options for all graph titles.

defaultEntityOpts :: Options

Hard-coded default options for all entities.

defaultHeaderOpts :: Options

Hard-coded default options for all entity headers.

defaultRelOpts :: Options

Hard-coded default options for all relationships.