1 "{ Package: 'stx:goodies/petitparser/compiler' }"

     2 

     3 "{ NameSpace: Smalltalk }"

     4 

     5 PEGFsaAbstractDeterminizator subclass:#PEGFsaChoiceDeterminizator

     6 	instanceVariableNames:''

     7 	classVariableNames:''

     8 	poolDictionaries:''

     9 	category:'PetitCompiler-FSA'

    10 !

    11 

    12 !PEGFsaChoiceDeterminizator methodsFor:'as yet unclassified'!

    13 

    14 determinize

    15     super determinize.

    16 

    17     fsa removeLowPriorityTransitions.

    18     fsa removeUnreachableStates.

    19     fsa removePriorities.

    20 !

    21 

    22 joinInfo: info with: anotherInfo into: newInfo

    23     "Merging into the failure"

    24     (info isFsaFailure and: [anotherInfo isFsaFailure not]) ifTrue: [  

    25         newInfo final: anotherInfo isFinal.

    26         newInfo priority: anotherInfo priority.

    27         newInfo failure: false.

    28         ^ self

    29     ].

    30     

    31     (anotherInfo isFsaFailure and: [info isFsaFailure not]) ifTrue: [  

    32         newInfo final: info isFinal.

    33         newInfo priority: (anotherInfo priority max: info priority).

    34         newInfo failure: false.

    35         ^ self

    36     ].

    37     

    38     (info hasEqualPriorityTo: anotherInfo) ifTrue: [ 

    39         newInfo final: (info isFinal or: [ anotherInfo isFinal ]).

    40         newInfo failure: (info isFsaFailure or: [anotherInfo isFailure]).

    41         newInfo priority: info priority.	

    42         ^ self

    43     ].

    44     

    45     (info hasHigherPriorityThan: anotherInfo) ifTrue: [ 

    46  		newInfo priority: info priority.	

    47         newInfo failure: info isFsaFailure.

    48         newInfo final: info isFinal.

    49         ^ self

    50     ].

    51 

    52     newInfo priority: anotherInfo priority.

    53     newInfo failure: anotherInfo isFsaFailure.

    54     newInfo final: anotherInfo isFinal.

    55 !

    56 

    57 joinState: state with: anotherState

    58     self assert: state isMultivalue not.

    59     self assert: anotherState isMultivalue not.

    60 

    61     ^ super joinState: state with: anotherState

    62 !

    63 

    64 joinTransitions: state with: anotherState into: newState

    65     self assert: newState isMultivalue not.

    66     

    67     newState transitions addAll: (state transitions collect: #copy).

    68     newState transitions addAll: (anotherState transitions collect: #copy).

    69     newState mergeTransitions.

    70 ! !

    71 

    72 !PEGFsaChoiceDeterminizator methodsFor:'joining'!

    73 

    74 joinRetval: state with: anotherState into: newState

    75     "Different retvals cannot merge their info"

    76     self assert: (state hasDifferentRetvalThan: anotherState) not. 

    77     self assert: state retval == anotherState retval.

    78 ! !

    79