CS 611 Lecture 13 Domain Constructions 9 /
نویسندگان
چکیده
Because loop-like constructs appear in programming languages so often, we need to take fixed points. In addition, because we are defining meaning functions inductively, most or all of the definitions for individual expression forms need to produce continuous functions. Therefore, we need to find an easy way to show that functions are continuous. We will define a restricted language so that all functions expressible in it are continuous. It’s a syntactic restriction on what functions we can write down. Functions (and other domain elements) defined in this language will look as though they are being defined by a programming language. However, there is no notion of evaluation for this language: the functions being defined simply are. The Meta-Language will look like a typed language, because we will explicitly indicate what domains meta-variables are members of. It’s not quite the same as the types that will show up in ordinary languages. For example, the ML pair type T1∗T2 is not modeled by the product domain T1×T2. The types in the source language are syntactic elements that can be mapped to domains; these domains have ordering relations defined on them. The Meta-language has a set of constructions that we can use to create new domains from existing ones.
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تاریخ انتشار 2000