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62 lines
2.7 KiB
Plaintext
62 lines
2.7 KiB
Plaintext
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Gofer 2.28 is an interactive functional programming environment (i.e. an
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interpreter) supporting a language based on the draft report for Haskell
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version 1.2, including the following features:
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o Lazy evaluation, higher order functions, pattern matching etc...
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o Wide range of built-in types with provision for defining new free
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datatypes and type synonyms.
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o Polymorphic type system with provision for overloading based on
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a system of type classes.
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o Full Haskell 1.2 expression and pattern syntax including lambda,
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case, conditional and let expressions, list comprehensions, operator
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sections, and wildcard, as and irrefutable patterns.
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o Partial implementation of Haskell 1.2 facilities for I/O, enabling
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the use of simple interactive programs and programs reading and writing
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text files.
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o User documentation, sample programs and source code freely available.
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o Supports constructor classes and overloaded monad comprehensions.
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o Simple minded compiler/translator Gofer -> C with runtime system for
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generation of standalone applications.
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o Runs (and originally developed) on PC compatible computers, but
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also works on Sun workstations. Code should be portable to many
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other kinds of machine.
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Gofer is intended as an experimental language, particularly where type classes
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are involved. Gofer extends the Haskell type class system in several ways:
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o Type classes with multiple parameters are supported.
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o Instances of type classes may be defined non-overlapping, but otherwise
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arbitrary types.
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o Predicates in contexts may involve arbitrary type expressions, not just
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type variables as in Haskell.
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o Basic approach to dictionary construction is different, based on the
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approach I described in a posting to the Haskell mailing list early in
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Feburary 1991. The resulting system ensures that all dictionaries are
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constructed before evaluation begins, avoiding repeated construction
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and enabling the shared evaluation of overloaded constants in
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dictionaries.
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The most significant features of Haskell not currently supported are:
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modules, arrays, overloaded numeric constants, default declarations, derived
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instances, contexts in datatype definitions.
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------------------------------------------------------------------------------
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And just in case you wondered:
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The name "Gofer" is not a trademark, registered or otherwise, and
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you are free to mention this name in published material, public and
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private correspondence, or other documents without restriction or
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obligation.
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