Class CloseableArgumentKeeping

java.lang.Object

org.ek9lang.compiler.phase5.CloseableArgumentKeeping

final class CloseableArgumentKeeping
extends Object

THE record of which constructor parameters a constructor KEEPS as a closeable property, and the deferred verdict on every construction that hands such a parameter a value that is not new (R4 of the fresh-store rule, E81062).

A constructor that stores its own parameter in a closeable property (held: res) takes ownership of the argument: the holder's operator close will close it. That is a transfer, and it is right only when the caller hands over a NEW value - Holder(Res("x")). Handing it a value that already has an owner - a try resource, a parameter, another object's property - gives that one resource two owners, and both close it (try -> res <- Res() / holder <- Holder(res) closed res twice).

Collected while every source is walked (Walk 1, in parallel), decided once all have been (check()): a constructor in one file is called in another, and a constructor that passes its own parameter on to super(...), this(...) or another keeping constructor keeps it too, which is a fixpoint over all of them. A member of a parameterised type is judged by the generic's own constructor (GenericTemplateMember).

Constructor Summary

Constructors

Constructor	Description
CloseableArgumentKeeping()

Method Summary

Modifier and Type	Method	Description
(package private) void	check()	After every source has been walked: close the kept set over the forwards, then report every construction that hands a kept parameter a value that is not new.
(package private) void	forwards(MethodSymbol constructor, int fromIndex, MethodSymbol target, int toIndex)	The constructor passes its own parameter at fromIndex to target at toIndex: if the target keeps it, so does this constructor.
(package private) void	keeps(MethodSymbol constructor, int index)	The constructor stores its parameter at index in a closeable property of the object it constructs.
(package private) void	notFresh(MethodSymbol target, int index, ErrorListener errorListener, IToken location, String argument)	A construction is given a closeable value that is not new at index: an error when the constructor keeps that parameter.

Methods inherited from class Object

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

Constructor Details

CloseableArgumentKeeping

CloseableArgumentKeeping()

Method Details

keeps

void keeps(MethodSymbol constructor,
 int index)

The constructor stores its parameter at index in a closeable property of the object it constructs.

forwards

void forwards(MethodSymbol constructor,
 int fromIndex,
 MethodSymbol target,
 int toIndex)

The constructor passes its own parameter at fromIndex to target at toIndex: if the target keeps it, so does this constructor.

notFresh

void notFresh(MethodSymbol target,
 int index,
 ErrorListener errorListener,
 IToken location,
 String argument)

A construction is given a closeable value that is not new at index: an error when the constructor keeps that parameter.

check

void check()

After every source has been walked: close the kept set over the forwards, then report every construction that hands a kept parameter a value that is not new.