"

 COPYRIGHT (c) 1989 by Claus Gittinger

	       All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

ClassDescription subclass:#Class

	instanceVariableNames:'name category classvars comment subclasses classFilename package

		revision primitiveSpec environment signature hook'

	classVariableNames:'OldMethods'

	poolDictionaries:''

	category:'Kernel-Classes'

!

!Class class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1989 by Claus Gittinger

	       All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

documentation

"

    Class adds more functionality to classes; minimum stuff has already

    been defined in Behavior and ClassDescription; this adds naming, categories etc.

    [Instance variables:]

        name            <Symbol>        the classes name

        category        <Symbol>        the classes category

        classvars       <String>        the names of the class variables

        comment         <String>        the classes comment; either a string,

                                        a number specifying the offset in classFilename, or nil

        subclasses      <Collection>    cached collection of subclasses

                                        (currently unused - but will be soon)

        classFilename   <String>        the file (or nil) where the classes

                                        sources are found 

        package         <Symbol>        the package, in which the class was defined

                                        (inserted by compilers)

        revision        <String>        revision string - inserted by stc

        primitiveSpec   <Array | nil>   describes primitiveIncludes, primitiveFunctions etc.

        environment     <Symbol | nil>  cached environment (i.e. Smalltalk or a namespace)

                                        of class

        signature       <SmallInteger>  the classes signature (used to detect obsolete

                                        or changed classes with binaryStorage)

                                        This is filled in lazy - i.e. upon the first signature query.

        hook            <any>           reserved: a place to add additional attributes,

                                        without a need to recompile all classes.

                                        Currently unused.

    [Class variables:]

        OldMethods                      if nonNil, this must be an IdentityDictionary,

                                        which is filled with method->previousversionMethod

                                        associations. Can be used for undo-last-method-change

                                        Notice: this may fillup your memory over time.

    WARNING: layout known by compiler and runtime system

    [author:]

        Claus Gittinger

    [see also:]

        Behavior ClassDescription Metaclass

"

! !

!Class class methodsFor:'Signal constants'!

methodRedefinitionSignal

    "return the signal raised when a method is about to be installed

     which redefines an existing method and the methods packages are not

     equal. This helps when filing in alien code, to prevent existing

     methods to be overwritten or redefined by incompatible methods"

    ^ MethodRedefinitionSignal

!

nameSpaceQuerySignal

    "return the signal used as an upQuery for the current nameSpace.

     Will be used when filing in code"

    ^ NameSpaceQuerySignal

    "

     Transcript showCR:Class nameSpaceQuerySignal raise

    "

    "Modified: 5.11.1996 / 20:08:38 / cg"

!

packageQuerySignal

    "return the signal used as an upQuery for the current packages name.

     Will be used when filing in code"

    ^ PackageQuerySignal

    "

     Transcript showCR:Class packageQuerySignal raise

    "

    "Created: 5.11.1996 / 20:07:22 / cg"

    "Modified: 5.11.1996 / 20:08:35 / cg"

!

updateChangeFileQuerySignal

    "return the signal used as an upQuery if the changeFile should be updated.

     If unhandled, the value of UpdatingChanges is returned by the signals

     static handler."

    ^ UpdateChangeFileQuerySignal

    "

     Transcript showCR:Class updateChangeFileQuerySignal raise

    "

    "Modified: 5.11.1996 / 20:08:44 / cg"

!

usedNameSpaceQuerySignal

    "return the signal used as an upQuery for the used nameSpace.

     Will be used when filing in code"

    ^ UsedNameSpaceQuerySignal

    "Created: 19.12.1996 / 23:57:27 / cg"

! !

!Class class methodsFor:'accessing - flags'!

catchMethodRedefinitions

    "return the redefinition catching flag."

    ^ CatchMethodRedefinitions

!

catchMethodRedefinitions:aBoolean

    "turn on/off redefinition catching. Return the prior value of the flag."

    |prev|

    prev := CatchMethodRedefinitions.

    CatchMethodRedefinitions := aBoolean.

    ^ prev

!

keepMethodHistory:aBoolean

    "turn on/off oldMethod remembering. If on, a methods previous version

     is kept locally, for later undo (or compare)."

    aBoolean ifTrue:[

        OldMethods isNil ifTrue:[

            OldMethods := IdentityDictionary new.

        ]

    ] ifFalse:[

        OldMethods := nil

    ].

    "

     Class keepMethodHistory:true

     Class keepMethodHistory:false

    "

    "Modified: 7.11.1996 / 18:36:00 / cg"

    "Created: 7.11.1996 / 19:05:57 / cg"

!

lockChangesFile

    "return true, if the change file is locked during update"

    ^ LockChangesFile

!

lockChangesFile:aBoolean

    "turn on/off change-file-locking. Return the previous value of the flag."

    |prev|

    prev := LockChangesFile.

    LockChangesFile := aBoolean.

    ^ prev

!

tryLocalSourceFirst

    ^ TryLocalSourceFirst

    "Created: 24.1.1996 / 19:55:35 / cg"

!

tryLocalSourceFirst:aBoolean

    TryLocalSourceFirst := aBoolean

    "Created: 24.1.1996 / 19:55:35 / cg"

!

updateChanges:aBoolean

    "turn on/off changes management. Return the prior value of the flag.

     This value is used as a default fallback - a querySignal handler may still 

     decide to return something else."

    |prev|

    prev := UpdatingChanges.

    UpdatingChanges := aBoolean.

    ^ prev

!

updatingChanges

    "return true if changes are recorded.

     The value returned here is the default fallback - a querySignal handler may still

     decide to return something else."

    ^ UpdatingChanges

! !

!Class class methodsFor:'accessing - history'!

flushMethodHistory

    "flush any method->previousVersion associations,

     all history is lost."

    OldMethods notNil ifTrue:[

        OldMethods := IdentityDictionary new

    ].

    "Created: 7.11.1996 / 19:07:25 / cg"

!

methodHistory

    "return a dictionary containing method->previousVersion associations,

     nil if method remembering has been turned off"

    ^ OldMethods 

    "

     Class oldMethods

    "

    "Modified: 7.11.1996 / 18:36:00 / cg"

    "Created: 7.11.1996 / 19:06:28 / cg"

! !

!Class class methodsFor:'helpers'!

revisionInfoFromString:aString

    "{ Pragma: +optSpace }"

    "return a dictionary filled with revision info.

     This extracts the relevant info from aString, asking

     the sourceCode manager (if there is one)"

    "

     For now, this is a bad design - since the sourceCodeManager

     is not always delivered, here, a fallBack is provided.

     (should probably deliver some RCS-header extractor in any case,

      even if no AbstractSourceCodeManager is present)

     (knowing about the details of RCS headers here is a bad design ...)

    "

    |words info nm mgr|

    "/

    "/ mhmh - ask the default manager

    "/

    (mgr := Smalltalk at:#SourceCodeManager) notNil ifTrue:[

        info := mgr revisionInfoFromString:aString.

        info notNil ifTrue:[

            ^ info

        ]

    ].

    "/

    "/ fallBack - handles some RCS headers only

    "/ is this really needed ?

    "/

    info := IdentityDictionary new.

    words := aString asCollectionOfWords.

    words notEmpty ifTrue:[

        "/

        "/ supported formats:

        "/

        "/ $-Header: pathName rev date time user state $

        "/ $-Revision: rev $

        "/ $-Id: fileName rev date time user state $

        "/

        ((words at:1) = '$Header:') ifTrue:[

            nm := words at:2.

            info at:#repositoryPathName put:nm.

            (nm endsWith:',v') ifTrue:[

                nm := nm copyWithoutLast:2

            ].

            info at:#fileName put:nm asFilename baseName.

            words size > 2 ifTrue:[

                (words at:3) = '$' ifFalse:[

                    info at:#revision put:(words at:3).

                    (words at:4) = '$' ifFalse:[

                        info at:#date put:(words at:4).

                        info at:#time put:(words at:5).

                        info at:#user put:(words at:6).

                        info at:#state put:(words at:7).

                    ]

                ].

            ].

            ^ info

        ].

        ((words at:1) = '$Revision:') ifTrue:[

            info at:#revision put:(words at:2).

            ^ info

        ].

        ((words at:1) = '$Id:') ifTrue:[

            info at:#fileName put:(words at:2).

            info at:#revision put:(words at:3).

            info at:#date put:(words at:4).

            info at:#time put:(words at:5).

            info at:#user put:(words at:6).

            info at:#state put:(words at:7).

            ^ info

        ].

    ].

    ^ nil

    "Created: 15.11.1995 / 14:58:35 / cg"

    "Modified: 29.1.1997 / 19:36:31 / cg"

!

revisionStringFromSource:aMethodSourceString

    "{ Pragma: +optSpace }"

    "extract a revision string from a methods source string"

    |lines line|

    lines := aMethodSourceString asCollectionOfLines.

    lines do:[:l |

        |i|

        i := l indexOfSubCollection:'$Header: '.

        i ~~ 0 ifTrue:[

            line := l copyFrom:i.

            i := line lastIndexOf:$$.

            i > 1 ifTrue:[

                line := line copyTo:i.

            ].

            ^ line

        ]

    ].

    ^ nil

    "Created: 15.10.1996 / 18:57:57 / cg"

    "Modified: 16.10.1996 / 16:54:40 / cg"

! !

!Class class methodsFor:'queries'!

isBuiltInClass

    "return true if this class is known by the run-time-system.

     Here, true is returned for myself, false for subclasses."

    ^ self == Class class or:[self == Class]

    "Created: 15.4.1996 / 17:17:13 / cg"

    "Modified: 23.4.1996 / 15:56:58 / cg"

! !

!Class methodsFor:'ST/V subclass creation'!

subclass:t instanceVariableNames:f classVariableNames:d poolDictionaries:s

    "{ Pragma: +optSpace }"

    "this method allows fileIn of ST/V classes 

     (which seem to have no category)"

    ^ self subclass:t 

           instanceVariableNames:f

           classVariableNames:d

           poolDictionaries:s

           category:'ST/V classes'

    "Modified: 5.1.1997 / 19:59:30 / cg"

!

variableByteSubclass:t classVariableNames:d poolDictionaries:s

    "{ Pragma: +optSpace }"

    "this method allows fileIn of ST/V variable byte classes 

     (which seem to have no category and no instvars)"

    ^ self variableByteSubclass:t 

           instanceVariableNames:''

           classVariableNames:d

           poolDictionaries:s

           category:'ST/V classes'

    "Modified: 5.1.1997 / 19:59:33 / cg"

!

variableSubclass:t instanceVariableNames:f classVariableNames:d poolDictionaries:s

    "{ Pragma: +optSpace }"

    "this method allows fileIn of ST/V variable pointer classes 

     (which seem to have no category)"

    ^ self variableSubclass:t 

           instanceVariableNames:f

           classVariableNames:d

           poolDictionaries:s

           category:'ST/V classes'

    "Modified: 5.1.1997 / 19:59:36 / cg"

! !

!Class methodsFor:'accessing'!

addClassVarName:aString

    "add a class variable if not already there and initialize it with nil.

     Also writes a change record and notifies dependents.

     BUG: Currently, no recompilation is done - this will change."

    (self classVarNames includes:aString) ifFalse:[

	self classVariableString:(self classVariableString , ' ' , aString).

	self addChangeRecordForClass:self.

	self changed:#definition.

    ]

    "Created: 29.10.1995 / 19:40:51 / cg"

!

category

    "return the category of the class. 

     The returned value may be a string or symbol."

    |owner|

    (owner := self owningClass) notNil ifTrue:[^ owner category].

    ^ category

    "

     Point category                

     Dictionary category           

    "

    "Modified: 15.10.1996 / 21:20:01 / cg"

    "Created: 1.4.1997 / 15:23:47 / stefan"

!

category:aStringOrSymbol

    "set the category of the class to be the argument, aStringOrSymbol"

    aStringOrSymbol isNil ifTrue:[

	category := aStringOrSymbol

    ] ifFalse:[

	category := aStringOrSymbol asSymbol

    ]

    "Created: 1.4.1997 / 15:24:04 / stefan"

!

classFilename

    "return the name of the file from which the class was compiled.

     This is currently NOT used."