Visitors Unchained
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چکیده
Traversing and transforming abstract syntax trees that involve name binding is notoriously di cult to do in a correct, concise, modular, customizable manner. We address this problem in the setting of OCaml, a functional programming language equipped with powerful object-oriented features. We use visitor classes as partial, composable descriptions of the operations that we wish to perform on abstract syntax trees. We introduce visitors, a simple type-directed facility for generating visitor classes that have no knowledge of binding. Separately, we present alphaLib, a library of small hand-written visitor classes, each of which knows about a speci c binding construct, a speci c representation of names, and/or a speci c operation on abstract syntax trees. By combining these components, a wide range of operations can be de ned. Multiple representations of names can be supported, as well as conversions between representations. Binding structure can be described either in a programmatic style, by writing visitor methods, or in a declarative style, via preprogrammed binding combinators.
منابع مشابه
Visitors Unchained
Traversing and transforming abstract syntax trees that involve name binding is notoriously difficult to do in a correct, concise, modular, customizable manner. We address this problem in the setting of OCaml, a functional programming language equipped with powerful object-oriented features. We use visitor classes as partial, composable descriptions of the operations that we wish to perform on a...
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