The specification of program flow in Madcap 6

ABSTRACT

The control structures of the Madcap language have evolved to a point where today those of Madcap 6 have obviated programmer defined labels and go-to statements. The benefits of the removal of these concepts are discussed in detail. Madcap has a powerful class of data structures, including sets, sequences, and expressions, along with a full array of operators for manipulating these structures. These operators include important facilities for forming sets and for forming and concatenating sequences, based on very general iterative expressions. Procedures in Madcap are expressions whose evaluation is deferred; characteristics of this approach are discussed. Also described is a notation which facilitates backtrack programming.

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INDEX TERMS

Keywords:
Bliss, Madcap, backtrack programming, co-routines, conditional expressions, control structures, expression language, go-to removal, iterative expressions, program flow, programmer defined labels, recursive procedures, set theory, two-dimensional language