28 lines
607 B
Smalltalk
28 lines
607 B
Smalltalk
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"
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A parser that succeeds only at the end of the input stream.
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"
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Class {
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#name : 'PPEndOfInputParser',
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#superclass : 'PPDelegateParser',
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#category : 'PetitParser-Parsers'
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}
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{ #category : 'operators' }
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PPEndOfInputParser >> end [
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^ self
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]
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{ #category : 'parsing' }
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PPEndOfInputParser >> parseOn: aPPContext [
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| memento result |
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memento := aPPContext remember.
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result := parser parseOn: aPPContext.
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(result isPetitFailure or: [ aPPContext stream atEnd ])
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ifTrue: [ ^ result ].
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result := PPFailure
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message: 'end of input expected'
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context: aPPContext.
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aPPContext restore: memento.
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^ result
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]
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