"

 COPYRIGHT (c) 1994 by Claus Gittinger

 COPYRIGHT (c) 2016 Jan Vrany

	      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.

"

"{ Package: 'stx:libcomp' }"

"{ NameSpace: Smalltalk }"

Object subclass:#Switch

	instanceVariableNames:'expressions values default'

	classVariableNames:''

	poolDictionaries:''

	category:'Programming-Support'

!

!Switch class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1994 by Claus Gittinger

 COPYRIGHT (c) 2016 Jan Vrany

	      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

    "

     OBSOLETE: do not use it, it is slow. You can also consider the Squeak extension Object>>#caseOf:

     from the libcompat package.

     This class provides a switch-expression facility.

     Consider this a demo example, nested if's are much more

     efficient.

     example:

        |a b|

        a := 1.

        b := 2.

        (Switch new)

            if:[a > b] then:['a is greater than b'];

            if:[a < b] then:['a is less than b'];

            otherwise:['a same as b'];

            value

    "

! !

!Switch class methodsFor:'instance creation'!

new

    ^ self basicNew initialize

! !

!Switch methodsFor:'cases'!

if:expr then:block

    expressions add:expr.

    values add:block

!

otherwise:block

    default := block

! !

!Switch methodsFor:'evaluation'!

value

    1 to:expressions size do:[:index |

	(expressions at:index) value ifTrue:[

	    ^ (values at:index) value

	]

    ].

    ^ default value

! !

!Switch methodsFor:'initialization'!

initialize

    expressions := OrderedCollection new.

    values := OrderedCollection new.

! !

!Switch class methodsFor:'documentation'!

version

    ^ '$Header: /cvs/stx/stx/libcomp/Switch.st,v 1.8 2013-08-06 09:50:31 stefan Exp $'

! !