20 lines
443 B
Smalltalk
20 lines
443 B
Smalltalk
Class {
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#name : 'PPPreviousParser',
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#superclass : 'PPDelegateParser',
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#category : 'PetitIslands-Extras'
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}
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{ #category : 'parsing' }
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PPPreviousParser >> parseOn: aPPContext [
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| result position |
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(aPPContext position > 0) ifTrue: [
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position := aPPContext position.
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aPPContext back.
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result := parser parseOn: aPPContext.
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aPPContext position: position.
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^ result
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].
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^ PPFailure message: 'At the beginning of a stream' at: 0
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]
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