Class SupersFirst

java.lang.Object

org.ek9lang.compiler.support.SupersFirst

public final class SupersFirst
extends Object

THE supers-first walk: act on every node of a set of sites AFTER everything it depends on, each node once.

The end-of-phase-2 post-passes (the sub-type constructors, the constrained types, sameness, inherited dispatchers, the field-less ?) all need "decide the super before the type below it", and each had copied the same started-set recursion (front-end rationalisation F28, A-5). They differ only in WHAT a node depends on, so that is the successors function: the super, the super and the traits, the constrained base.

• Only nodes that are among the roots are acted on; a successor that is not one (a built-in super, a type of another kind) is skipped, not walked into.
• Each node is marked BEFORE its successors are visited, so a loop in a broken hierarchy stops here - the hierarchy checks that follow report it.
• Nodes are keyed by IDENTITY, never by equals/hashCode. The passes MUTATE the symbol they key on - a completed operator, an inherited-dispatcher marker, a linked super - and AggregateSymbol.hashCode reads mutable state, so a hash-keyed set could lose an entry mid-walk or merge two distinct symbols that compare equal by structure. (The old comments said the hash walks the super chain; it no longer does - FE41/FE51 - but identity is still the right key.)

Method Summary

Modifier and Type	Method	Description
static <T> void	forEach(Collection<? extends T> roots, Function<? super T, ? extends Collection<? extends T>> successors, Consumer<? super T> act)	Visit every root, each after its successors, once.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

forEach

public static <T> void forEach(Collection<? extends T> roots,
 Function<? super T, ? extends Collection<? extends T>> successors,
 Consumer<? super T> act)

Visit every root, each after its successors, once. Roots are visited in the order given.

Parameters:

roots - the nodes to act on, in the order to start from; also the only nodes ever acted on

successors - what a node must be acted on after (the super, the traits, a constrained base)

act - the action