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MergeConditionals

This is Filter Equivalent. This function may be present in generated code, but should not be used in hand-written code.

Header:	STD.h
Namespace:	fil
Module:	FoundationLite

Returns the first not-Nil input object.

Syntax

void fil::MergeConditionals
(
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject1,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject2,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject3,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject4,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject5,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject6,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject7,
	const typename ftl::ToConditionalType<const Type&>::Type& inConditionalObject8,
	typename ftl::ToConditionalType<Type>::Type& outConditionalObject
)

Parameters

Name	Type	Description
inConditionalObject1	const typename ToConditionalType<const Type&>::Type&	First conditional input object
inConditionalObject2	const typename ToConditionalType<const Type&>::Type&	Second conditional input object
inConditionalObject3	const typename ToConditionalType<const Type&>::Type&	Third conditional input object
inConditionalObject4	const typename ToConditionalType<const Type&>::Type&	Fourth conditional input object
inConditionalObject5	const typename ToConditionalType<const Type&>::Type&	Fifth conditional input object
inConditionalObject6	const typename ToConditionalType<const Type&>::Type&	Sixth conditional input object
inConditionalObject7	const typename ToConditionalType<const Type&>::Type&	Seventh conditional input object
inConditionalObject8	const typename ToConditionalType<const Type&>::Type&	Eighth conditional input object
outConditionalObject	typename ToConditionalType<Type>::Type&	The first of the input objects that exists or nothing

Description

The MergeConditionals function is related to Conditional<T>. The operation collects a number of conditional objects and passes the first of the existing input values onto the outObject output. If all of the input values are Nil, the outObject is set to Nil.

The operation is similar to MergeBranches, yet it computes a conditional object, and thus does not require that at least one of the input values is not-Nil.

Hints

Also consider the coalescing operator (??) in Formula Blocks.
This filter creates a full copy of one of the input objects. Thus, if you need the highest possible speed, use this filter only with primitive types. An alternative is to use Variant Step macrofilters which are fast and elegant.

Examples


inConditionalObject1 = Nil inConditionalObject2 = Nil inConditionalObject3 = "Mike" inConditionalObject4 = "Alice" inConditionalObject5 = Nil inConditionalObject6 = "Joanne" inConditionalObject7 = Nil inConditionalObject8 = Nil	outConditionalObject = "Mike"