Safe Haskell	Safe-Inferred
Language	Haskell98

Development.Flo

Contents

Types
Functions

Description

Generate a flow chart by from annotations from a code base.

The syntax is as follows:

 expr  <- label / next / do / if / task
 label <- "label" name
 task  <- "task" text
 next  <- "next" name / "trigger" name
 do    <- "do" text
 if    <- "if" name "\n" "then" name ("\n" "else" name)?

where name and text are both arbitrary text.

A label is used to label a node in the graph. next is used to link the current node to another node by its label. The text for a node is written by do, which explains what this node does, or by using if which makes this node a conditional which goes to one of two possible nodes.

Example (assuming \/\// to be the declaration prefix):

 /// label main
 /// if Logged in?
 /// then display_overview
 /// else display_login
 /// label display_overview
 /// do Display overview.
 /// next display_event
 /// next display_paper
 // Event list code here.
 event_list();
 /// label display_login
 /// do Display login.
 /// next try_login
 // Login display code here.
 display_login();
 /// label try_login
 /// do Check login.
 /// next main
 /// trigger log_access_time
 // Login attempt code here.
 if(check_login()) log_attempt_success();
 /// label display_event
 /// do Display a single event.
 /// next display_paper
 // Event list code here.
 display_event();
 /// label display_paper
 /// do Display a single paper.
 // Paper display code here.
 display_paper();
 /// label log_access_time
 /// task Log login accesses.
 log_login();

In other words: You have a main page which either displays a login screen or lists the user's events if logged in. From the events page you can get to the event page.

Custom syntax can be used, too. Example:

 {- # bar -}
SELECT * FROM mysql;

Synopsis

Types

data Node Source

A workflow node.

Constructors

Node
Fields nodeName :: Name nodeEdges :: [Edge] nodeDesc :: String nodeType :: Type

Instances

Show Node

data Type Source

Type of the node.

Constructors

Action
Condition
Background

Instances

Enum Type
Eq Type
Show Type

data Edge Source

A workflow connection.

Constructors

Edge
Fields edgeLabel :: String edgeTo :: Name

Instances

Show Edge

data Decl Source

A workflow declaration.

Constructors

Label Name	Sets the current node.
Next Name	Links to a next node (an edge).
Do String	Describes this node.
Task String	Run some task (create db entry, delete file, send email etc.).
If String Name (Maybe Name)	Makes this node a conditional.

Instances

Show Decl

data Name Source

A node name.

Instances

Eq Name
Show Name

Functions

digraph :: String -> String Source

Wrap a string up in a digraph.

nodesToDot :: [Node] -> String Source

Convert a list of nodes to a Graphviz dot document.

declsToNodes :: [Decl] -> [Node] Source

Converts a list of declarations to a list of nodes.

parseFile :: FilePath -> String -> Maybe String -> IO (Either ParseError [Decl]) Source

Parse a source file containing commented declarations.