16 lines
347 B
Smalltalk
16 lines
347 B
Smalltalk
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"
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A parser that optionally parsers its delegate, or answers nil.
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"
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Class {
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#name : 'PPOptionalParser',
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#superclass : 'PPDelegateParser',
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#category : 'PetitParser-Parsers'
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}
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{ #category : 'parsing' }
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PPOptionalParser >> parseOn: aPPContext [
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| element |
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element := parser parseOn: aPPContext.
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^ element isPetitFailure ifFalse: [ element ]
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]
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