Curry: An Integrated Functional Logic Language

SimplePattern ::= VariableID | _
| QDataConstrID
| Literal
| ()
| ( Pattern1 , . . . , Patternn ) (n > 1)
| ( Pattern )
| [ Pattern1 , . . . , Patternn ] (n � 0)
VariableID ::= see lexicon
LocalDefs ::= {ValueDeclaration1 ; . . . ; ValueDeclarationn } (n > 0)
ValueDeclaration ::= FunctionDeclaration
| PatternDeclaration
| VariableID1 , . . . , VariableIDn free (n � 0)
PatternDeclaration ::= Pattern = Expr [where LocalDefs]
CondExprs ::= | Expr = Expr [CondExprs]
Expr ::= \ SimplePattern1 . . . SimplePatternn -> Expr (n > 0)
| let LocalDefs in Expr (let expression)
| if Expr then Expr else Expr (conditional)
| case Expr of {Alt1 ; . . . ; Altn } (case expression, n � 0)
| do {Stmt1 ; . . . ; Stmtn ; Expr } (do expression, n � 0)
| Expr QInfixOpID Expr (infix operator)
| - Expr (unary minus)
| FunctExpr
FunctExpr ::= [FunctExpr] BasicExpr (function application)
BasicExpr ::= QVariableID (variable)
| QDataConstrID (data constructor)
| QFunctionID (defined function)
| ( QInfixOpID ) (operator function)
| Literal
| () (empty tuple)
| ( Expr ) (parenthesized expression)
| ( Expr1 , . . . , Exprn ) (tuple, n > 1)
| [ Expr1 , . . . , Exprn ] (finite list, n � 0)
| [ Expr [, Expr] .. [Expr] ] (arithmetic sequence)
| [ Expr | Qual1 , . . . , Qualn ] (list comprehension, n � 1)
| ( Expr QInfixOpID ) (left section)
| ( QInfixOpID Expr ) (right section)
Alt ::= Pattern -> Expr
Qual ::= Expr
| Pattern