Exempel på eliminator

• These dispatch functions are never actually applied; in most cases, the dead-code eliminator will remove them.

• The -construct splits a programming problem into subproblems given an arbitrary eliminator.

• In the absence of perfect eliminators, the following heuristics can be used.

• A key point of this paper is that the types of eliminators give an abstract interface to pattern analysis, whatever the actual patterns are.

• So we are looking for maximal eliminators, ideally perfect ones.

• A test is a perfect eliminator if it is an eliminator of k - 1 sequences.

• However, practice has shown that eliminators are rather cumbersome to use, whereas case-expressions and fixpoint expressions lead to more concise and readable definitions.

• Although eliminators are higher-order functions, section 6 introduces a first-order programming idiom for constructing and working with them - this is our notion of views.

• We shall present more sophisticated examples in section 6, where we develop an idiom for constructing non-standard eliminators by first-order programming.

• We put the targets first, so that an elimination operator is a function from targets to eliminators.

• It is easy to extract these eliminators from programs like compare above.

• As a tie-breaker, a top-down, left-toright order of selecting maximal eliminators is followed.

• In section 4 we give a technical characterization of eliminators, together with the ('by') construct which supports their use, whether primitive or user-defined.

• If a perfect eliminator exists each time the select action procedure is called, then the size of the tree automaton will be linear in the total number of actions.

• Such actions, called eliminators, are defined below.