org.erights.e.elang.visitors
Class AlphaRenameVisitor

java.lang.Object
  |
  +--org.erights.e.elang.visitors.KernelECopyVisitor
        |
        +--org.erights.e.elang.visitors.AlphaRenameVisitor

All Implemented Interfaces:

ETreeVisitor

public class AlphaRenameVisitor

extends KernelECopyVisitor

Untamed: Like RenameVisitor, but does an 'alpha-renaming'.

An alpha renaming gives each distinct variable a unique name. Since we are not in control of top-level names, we rename exactly variables defined in nested scope boxes. We use a HilbertHotel to generate new names and to transform old ones. In order to deal with the varName problem in the varName way, we will transform top-level names according to the varName rename(). Since AlphaRenameVisitor needs to treat the expression top level specially, that's represented by a null 'myOptRenamings'. Assuming that top-level names should avoid being of a form that rename might relocate (ie, the form of name generated by newTemp()), then, by turning *all* non top-level names into this form, these won't conflict with such well formed top-level names. This is a bit of a kludge. Perhaps we should treat relocated top level names as an error?

Author:

Mark S. Miller

Field Summary

private HilbertHotel	myHilbert
private FlexMap	myOptRenamings

Fields inherited from class org.erights.e.elang.visitors.KernelECopyVisitor

Constructor Summary

AlphaRenameVisitor()
Enabled:

AlphaRenameVisitor(ETreeVisitor decorator)
Enabled:

Method Summary

private FlexMap	fork()
private FlexMap	innerRenames()
Object	visitCatchExpr(CatchExpr optOriginal, EExpr attempt, Pattern patt, EExpr catcher) Enabled:
Object	visitEMethod(ENode optOriginal, String docComment, String verb, Pattern[] patterns, EExpr returnGuard, EExpr body) Enabled:
Object	visitEscapeExpr(ENode optOriginal, Pattern hatch, EExpr body) Enabled:
Object	visitFinallyExpr(FinallyExpr optOriginal, EExpr attempt, EExpr unwinder) Enabled:
Object	visitFinalPattern(ENode optOriginal, String varName, EExpr valueGuardExpr) Enabled:
Object	visitHideExpr(ENode optOriginal, EExpr body) Enabled:
Object	visitIfExpr(IfExpr optOriginal, EExpr test, EExpr then, EExpr els) Enabled:
Object	visitMatcher(ENode optOriginal, Pattern patt, EExpr body) Enabled:
Object	visitNounExpr(ENode optOriginal, String varName) Enabled:
Object	visitVarPattern(ENode optOriginal, String varName, EExpr slotGuardExpr) Enabled:

Methods inherited from class org.erights.e.elang.visitors.KernelECopyVisitor

nest, optSpan, run, visitAssignExpr, visitCallExpr, visitCatchExpr, visitCdrPattern, visitDefineExpr, visitEScript, visitFinallyExpr, visitIfExpr, visitIgnorePattern, visitListPattern, visitLiteralExpr, visitMatchBindExpr, visitObjectExpr, visitQuasiLiteralExpr, visitQuasiLiteralPatt, visitQuasiPatternExpr, visitQuasiPatternPatt, visitScopeExpr, visitSendExpr, visitSeqExpr, visitSlotExpr, visitSuchThatPattern, xformEExpr, xformEExprs, xformEScript, xformMatcher, xformMethod, xformNode, xformPattern, xformPatterns

Methods inherited from class java.lang.Object

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

Field Detail

myOptRenamings

private FlexMap myOptRenamings

myHilbert

private final HilbertHotel myHilbert

Constructor Detail

AlphaRenameVisitor

public AlphaRenameVisitor(ETreeVisitor decorator)

Enabled:

AlphaRenameVisitor

public AlphaRenameVisitor()

Enabled:

Method Detail

fork

private FlexMap fork()

innerRenames

private FlexMap innerRenames()

visitNounExpr

public Object visitNounExpr(ENode optOriginal,
                            String varName)

Enabled:

Specified by:

visitNounExpr in interface ETreeVisitor

Overrides:

visitNounExpr in class KernelECopyVisitor

See Also:

The Kernel-E Noun Expression

visitFinalPattern

public Object visitFinalPattern(ENode optOriginal,
                                String varName,
                                EExpr valueGuardExpr)

Enabled:

Specified by:

visitFinalPattern in interface ETreeVisitor

Overrides:

visitFinalPattern in class KernelECopyVisitor

See Also:

The Kernel-E Final Pattern

visitVarPattern

public Object visitVarPattern(ENode optOriginal,
                              String varName,
                              EExpr slotGuardExpr)

Enabled:

Specified by:

visitVarPattern in interface ETreeVisitor

Overrides:

visitVarPattern in class KernelECopyVisitor

See Also:

The Kernel-E Var Pattern

visitEscapeExpr

public Object visitEscapeExpr(ENode optOriginal,
                              Pattern hatch,
                              EExpr body)

Enabled:

Specified by:

visitEscapeExpr in interface ETreeVisitor

Overrides:

visitEscapeExpr in class KernelECopyVisitor

See Also:

The Kernel-E Escape Expression

visitHideExpr

public Object visitHideExpr(ENode optOriginal,
                            EExpr body)

Enabled:

Specified by:

visitHideExpr in interface ETreeVisitor

Overrides:

visitHideExpr in class KernelECopyVisitor

See Also:

The Kernel-E Hide Expression

visitIfExpr

public Object visitIfExpr(IfExpr optOriginal,
                          EExpr test,
                          EExpr then,
                          EExpr els)

Enabled:

visitCatchExpr

public Object visitCatchExpr(CatchExpr optOriginal,
                             EExpr attempt,
                             Pattern patt,
                             EExpr catcher)

Enabled:

visitFinallyExpr

public Object visitFinallyExpr(FinallyExpr optOriginal,
                               EExpr attempt,
                               EExpr unwinder)

Enabled:

visitEMethod

public Object visitEMethod(ENode optOriginal,
                           String docComment,
                           String verb,
                           Pattern[] patterns,
                           EExpr returnGuard,
                           EExpr body)

Enabled:

Specified by:

visitEMethod in interface ETreeVisitor

Overrides:

visitEMethod in class KernelECopyVisitor

See Also:

The Kernel-E Method Node

visitMatcher

public Object visitMatcher(ENode optOriginal,
                           Pattern patt,
                           EExpr body)

Enabled:

Specified by:

visitMatcher in interface ETreeVisitor

Overrides:

visitMatcher in class KernelECopyVisitor

See Also:

The Kernel-E Matcher Node