30 lines
828 B
GDScript3
30 lines
828 B
GDScript3
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static func single_(
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predicate = null
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) -> Callable:
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# """Returns the only element of an observable sequence that satisfies the
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# condition in the optional predicate, and reports an error if there
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# is not exactly one element in the observable sequence.
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#
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# Example:
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# >>> var res = GDRx.op.single()
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# >>> var res = GDRx.op.single(func(x): return x == 42)
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#
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# Args:
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# predicate -- [Optional] A predicate function to evaluate for
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# elements in the source sequence.
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#
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# Returns:
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# An observable sequence containing the single element in the
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# observable sequence that satisfies the condition in the predicate.
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# """
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if predicate != null:
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var _predicate : Callable = predicate
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return GDRx.pipe.compose2(
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GDRx.op.filter(_predicate),
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GDRx.op.single()
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)
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else:
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return GDRx.op.single_or_default_async(false)
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