-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Utilities for parsing and evaluating mathematical expressions.
--   
--   ParserFunction provides utilities for parsing and evaluating
--   mathematical expressions. The central parsing function in this package
--   is <tt>stringToExpr</tt>, which parses a string-expression (e.g.
--   "3*x+2") and returns a Maybe expression tree of type Expr (e.g. Just
--   (Add (Mul (Num 3.0) (Var 'x')) (Num 2.0))). This type is suitable for
--   performing symbolic logic. Expressions can then be evaluated using the
--   function <tt>evaluate</tt> (e.g. <tt>evaluate</tt> (fromAscList
--   [("x",2)]) (Add (Mul (Num 3.0) (Var 'x'))) (Num 2.0) would give 8.0).
--   If you wish to evaluate a string-expression without any intermediate
--   symbolic logic operations, simply use the function
--   <tt>evaluateExpression</tt> (e.g. <tt>evaluateExpression</tt> "3*x+2"
--   [('x',4)] gives 14.0). More examples of these functions can be found
--   by viewing the source code for this package.
@package ParserFunction
@version 0.0.6

module Text.ParserCombinators.Parsec.ParserFunction

-- | The Expr data type provides a basis for ordering mathematical
--   operations.
data Expr

-- | <tt>evaluateExpression</tt> evaluates a mathematical expression s
--   using the variable map m.
evaluateExpression :: String -> [(Char, Double)] -> Double

-- | <tt>stringToExpr</tt> parses an expression and returns an expression
--   tree of type Expr.
stringToExpr :: String -> Maybe Expr
buildExpr :: Parser Expr
expressionTable :: [[Operator Char st Expr]]
factor :: Parser Expr
variables :: Parser Expr
number :: Parser Expr

-- | <tt>evaluate</tt> takes a map and expression tree to produce a
--   numerical value.
evaluate :: Map String Double -> Expr -> Double
instance Show Expr
instance Eq Expr
instance Ord Expr