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A Curry module in the intermediate form. A value of this type has the form CurryProg modname imports dfltdecl clsdecls instdecls typedecls funcdecls opdecls where [modname] Name of this module [imports] List of modules names that are imported [dfltdecl] Optional default declaration [clsdecls] Class declarations [instdecls] Instance declarations [typedecls] Type declarations [funcdecls] Function declarations [opdecls] Operator precedence declarations

A module name.

A qualified name. In AbstractCurry all names are qualified to avoid name clashes. The first component is the module name and the second component the unqualified name as it occurs in the source program.

Data type to specify the visibility of various entities.

The type for representing type variables. They are represented by (i,n) where i is a type variable index which is unique inside a function and n is a name (if possible, the name written in the source program).

Default declaration.

Definitions of type classes. A type class definition of the form class cx => c a where { ...;f :: t;... } is represented by the Curry term (CClass c v cx tv [...(CFunc f ar v t [...,CRule r,...])...]) where tv is the index of the type variable a and v is the visibility of the type class resp. method. Note: The type variable indices are unique inside each class declaration and are usually numbered from 0. The methods' types share the type class' type variable index as the class variable has to occur in a method's type signature. The list of rules for a method's declaration may be empty if no default implementation is provided. The arity ar is determined by a given default implementation or 0. Regardless of whether typed or untyped abstract curry is generated, the methods' declarations are always typed.

Definitions of instances. An instance definition of the form instance cx => c ty where { ...;fundecl;... } is represented by the Curry term (CInstance c cx ty [...fundecl...]) Note: The type variable indices are unique inside each instance declaration and are usually numbered from 0. The methods' types use the instance's type variable indices (if typed abstract curry is generated).

Definitions of algebraic data types and type synonyms. A data type definition of the form data t x1...xn = ...| forall y1...ym . cx => c t1....tkc |... deriving (d1,...,dp) is represented by the Curry term (CType t v [i1,...,in] [...(CCons [l1,...,lm] cx c kc v [t1,...,tkc])...] [d1,...,dp]) where each ij is the index of the type variable xj, each lj is the index of the existentially quantified type variable yj and v is the visibility of the type resp. constructor. Note: The type variable indices are unique inside each type declaration and are usually numbered from 0. Thus, a data type declaration consists of the name of the data type, a list of type parameters and a list of constructor declarations.

A constructor declaration consists of a list of existentially quantified type variables, a context, the name of the constructor and a list of the argument types of the constructor. The arity equals the number of types.

A record field declaration consists of the name of the the label, the visibility and its corresponding type.

The type for representing a class constraint.

The type for representing a context.

Type expression. A type expression is either a type variable, a function type, a type constructor or a type application.

Qualified type expression.

Operator precedence declaration. An operator precedence declaration fix p n in Curry corresponds to the AbstractCurry term (COp n fix p).

Fixity declarations of infix operators

Function arity

Data type for representing function declarations. A function declaration in FlatCurry is a term of the form (CFunc name arity visibility type (CRules eval [CRule rule1,...,rulek])) and represents the function name with definition name :: type rule1 ... rulek Note: The variable indices are unique inside each rule. External functions are represented as (CFunc name arity type (CExternal s)) where s is the external name associated to this function. Thus, a function declaration consists of the name, arity, type, and a list of rules. If the list of rules is empty, the function is considered to be externally defined.

Right-hand-side of a CRule or an case expression

The general form of a function rule. It consists of a list of patterns (left-hand side), a list of guards (success if not present in the source text) with their corresponding right-hand sides, and a list of local declarations.

Local (let/where) declarations

Variable names. Object variables occurring in expressions are represented by (Var i) where i is a variable index.

Curry expressions.

Type of case expressions

Statements in do expressions and list comprehensions.

Pattern expressions.

Literals occurring in an expression or a pattern, either an integer, a float, a character, or a string constant. Note: The constructor definition of CIntc differs from the original PAKCS definition. It uses Haskell type Integer instead of Int to provide an unlimited range of integer numbers. Furthermore, float values are represented with Haskell type Double instead of Float to gain double precision.

Labeled record fields

Current version of AbstractCurry