Join.h

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// Copyright Epic Games, Inc. All Rights Reserved.
 
#pragma once
 
#include "CoreTypes.h"
#include "Containers/StringView.h"
#include "Misc/StringBuilder.h"
#include "Templates/IdentityFunctor.h"
#include "Templates/Invoke.h"
#include "Templates/Tuple.h"
 
namespace UE::String::Private
{
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename QuoteType>
struct TJoinQuotedBy
{
    RangeType&& Range;
    ProjectionType Projection;
    DelimiterType&& Delimiter;
    QuoteType&& Quote;
};
 
template <typename RangeType, typename ProjectionType, typename DelimiterType>
struct TJoinBy
{
    RangeType&& Range;
    ProjectionType Projection;
    DelimiterType&& Delimiter;
};
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename QuoteType>
struct TJoinTupleQuotedBy
{
    TupleType&& Tuple;
    ProjectionType Projection;
    DelimiterType&& Delimiter;
    QuoteType&& Quote;
};
 
template <typename TupleType, typename ProjectionType, typename DelimiterType>
struct TJoinTupleBy
{
    TupleType&& Tuple;
    ProjectionType Projection;
    DelimiterType&& Delimiter;
};
 
} // UE::String::Private
 
namespace UE::String
{
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename QuoteType>
inline auto JoinQuotedBy(RangeType&& Range, ProjectionType Projection, DelimiterType&& Delimiter, QuoteType&& Quote)
    -> Private::TJoinQuotedBy<RangeType, ProjectionType, DelimiterType, QuoteType>
{
    return {Forward<RangeType>(Range), MoveTemp(Projection), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote)};
}
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename QuoteType, typename CharType>
inline TStringBuilderBase<CharType>& JoinQuotedByTo(
    RangeType&& Range,
    ProjectionType Projection,
    DelimiterType&& Delimiter,
    QuoteType&& Quote,
    TStringBuilderBase<CharType>& Builder)
{
    bool bFirst = true;
    for (auto&& Elem : Forward<RangeType>(Range))
    {
        if (bFirst)
        {
            bFirst = false;
        }
        else
        {
            Builder << Delimiter;
        }
        Builder << Quote << Invoke(Projection, Elem) << Quote;
    }
    return Builder;
}
 
template <typename RangeType, typename DelimiterType, typename QuoteType>
inline auto JoinQuoted(RangeType&& Range, DelimiterType&& Delimiter, QuoteType&& Quote)
    -> Private::TJoinQuotedBy<RangeType, FIdentityFunctor, DelimiterType, QuoteType>
{
    return {Forward<RangeType>(Range), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote)};
}
 
template <typename RangeType, typename DelimiterType, typename QuoteType, typename CharType>
inline TStringBuilderBase<CharType>& JoinQuotedTo(
    RangeType&& Range,
    DelimiterType&& Delimiter,
    QuoteType&& Quote,
    TStringBuilderBase<CharType>& Builder)
{
    return JoinQuotedByTo(Forward<RangeType>(Range), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote), Builder);
}
 
template <typename RangeType, typename ProjectionType, typename DelimiterType>
inline auto JoinBy(RangeType&& Range, ProjectionType Projection, DelimiterType&& Delimiter)
    -> Private::TJoinBy<RangeType, ProjectionType, DelimiterType>
{
    return {Forward<RangeType>(Range), MoveTemp(Projection), Forward<DelimiterType>(Delimiter)};
}
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename CharType>
inline TStringBuilderBase<CharType>& JoinByTo(
    RangeType&& Range,
    ProjectionType Projection,
    DelimiterType&& Delimiter,
    TStringBuilderBase<CharType>& Builder)
{
    bool bFirst = true;
    for (auto&& Elem : Forward<RangeType>(Range))
    {
        if (bFirst)
        {
            bFirst = false;
        }
        else
        {
            Builder << Delimiter;
        }
        Builder << Invoke(Projection, Elem);
    }
    return Builder;
}
 
template <typename RangeType, typename DelimiterType>
inline auto Join(RangeType&& Range, DelimiterType&& Delimiter)
    -> Private::TJoinBy<RangeType, FIdentityFunctor, DelimiterType>
{
    return {Forward<RangeType>(Range), FIdentityFunctor(), Forward<DelimiterType>(Delimiter)};
}
 
template <typename RangeType, typename DelimiterType, typename CharType>
inline TStringBuilderBase<CharType>& JoinTo(RangeType&& Range, DelimiterType&& Delimiter, TStringBuilderBase<CharType>& Builder)
{
    return JoinByTo(Forward<RangeType>(Range), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Builder);
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename QuoteType>
inline auto JoinTupleQuotedBy(TupleType&& Tuple, ProjectionType Projection, DelimiterType&& Delimiter, QuoteType&& Quote)
    -> Private::TJoinTupleQuotedBy<TupleType, ProjectionType, DelimiterType, QuoteType>
{
    return {Forward<TupleType>(Tuple), MoveTemp(Projection), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote)};
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename QuoteType, typename CharType
    UE_REQUIRES(TIsTuple_V<std::decay_t<TupleType>>)>
inline TStringBuilderBase<CharType>& JoinTupleQuotedByTo(
    TupleType&& Tuple,
    ProjectionType Projection,
    DelimiterType&& Delimiter,
    QuoteType&& Quote,
    TStringBuilderBase<CharType>& Builder)
{
    bool bFirst = true;
    VisitTupleElements([&bFirst, &Projection, &Delimiter, &Quote, &Builder](auto&& Elem)
    {
        if (bFirst)
        {
            bFirst = false;
        }
        else
        {
            Builder << Delimiter;
        }
        Builder << Quote << Invoke(Projection, Elem) << Quote;
    }, Tuple);
    return Builder;
}
 
template <typename TupleType, typename DelimiterType, typename QuoteType>
inline auto JoinTupleQuoted(TupleType&& Tuple, DelimiterType&& Delimiter, QuoteType&& Quote)
    -> Private::TJoinTupleQuotedBy<TupleType, FIdentityFunctor, DelimiterType, QuoteType>
{
    return {Forward<TupleType>(Tuple), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote)};
}
 
template <typename TupleType, typename DelimiterType, typename QuoteType, typename CharType>
inline TStringBuilderBase<CharType>& JoinTupleQuotedTo(
    TupleType&& Tuple,
    DelimiterType&& Delimiter,
    QuoteType&& Quote,
    TStringBuilderBase<CharType>& Builder)
{
    return JoinTupleQuotedByTo(Forward<TupleType>(Tuple), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Forward<QuoteType>(Quote), Builder);
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType>
inline auto JoinTupleBy(TupleType&& Tuple, ProjectionType Projection, DelimiterType&& Delimiter)
    -> Private::TJoinTupleBy<TupleType, ProjectionType, DelimiterType>
{
    return {Forward<TupleType>(Tuple), MoveTemp(Projection), Forward<DelimiterType>(Delimiter)};
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename CharType
    UE_REQUIRES(TIsTuple_V<std::decay_t<TupleType>>)>
inline TStringBuilderBase<CharType>& JoinTupleByTo(
    TupleType&& Tuple,
    ProjectionType Projection,
    DelimiterType&& Delimiter,
    TStringBuilderBase<CharType>& Builder)
{
    bool bFirst = true;
    VisitTupleElements([&bFirst, &Projection, &Delimiter, &Builder](auto&& Elem)
    {
        if (bFirst)
        {
            bFirst = false;
        }
        else
        {
            Builder << Delimiter;
        }
        Builder << Invoke(Projection, Elem);
    }, Tuple);
    return Builder;
}
 
template <typename TupleType, typename DelimiterType>
inline auto JoinTuple(TupleType&& Tuple, DelimiterType&& Delimiter)
    -> Private::TJoinTupleBy<TupleType, FIdentityFunctor, DelimiterType>
{
    return {Forward<TupleType>(Tuple), FIdentityFunctor(), Forward<DelimiterType>(Delimiter)};
}
 
template <typename TupleType, typename DelimiterType, typename CharType>
inline TStringBuilderBase<CharType>& JoinTupleTo(TupleType&& Tuple, DelimiterType&& Delimiter, TStringBuilderBase<CharType>& Builder)
{
    return JoinTupleByTo(Forward<TupleType>(Tuple), FIdentityFunctor(), Forward<DelimiterType>(Delimiter), Builder);
}
 
} // UE::String
 
namespace UE::String::Private
{
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename QuoteType, typename CharType>
inline TStringBuilderBase<CharType>& operator<<(
    TStringBuilderBase<CharType>& Builder,
    Private::TJoinQuotedBy<RangeType, ProjectionType, DelimiterType, QuoteType>&& Adapter)
{
    return JoinQuotedByTo(
        Forward<RangeType>(Adapter.Range),
        MoveTemp(Adapter.Projection),
        Forward<DelimiterType>(Adapter.Delimiter),
        Forward<QuoteType>(Adapter.Quote),
        Builder);
}
 
template <typename RangeType, typename ProjectionType, typename DelimiterType, typename CharType>
inline TStringBuilderBase<CharType>& operator<<(
    TStringBuilderBase<CharType>& Builder,
    Private::TJoinBy<RangeType, ProjectionType, DelimiterType>&& Adapter)
{
    return JoinByTo(Forward<RangeType>(Adapter.Range), MoveTemp(Adapter.Projection), Forward<DelimiterType>(Adapter.Delimiter), Builder);
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename QuoteType, typename CharType>
inline TStringBuilderBase<CharType>& operator<<(
    TStringBuilderBase<CharType>& Builder,
    Private::TJoinTupleQuotedBy<TupleType, ProjectionType, DelimiterType, QuoteType>&& Adapter)
{
    return JoinTupleQuotedByTo(
        Forward<TupleType>(Adapter.Tuple),
        MoveTemp(Adapter.Projection),
        Forward<DelimiterType>(Adapter.Delimiter),
        Forward<QuoteType>(Adapter.Quote),
        Builder);
}
 
template <typename TupleType, typename ProjectionType, typename DelimiterType, typename CharType>
inline TStringBuilderBase<CharType>& operator<<(
    TStringBuilderBase<CharType>& Builder,
    Private::TJoinTupleBy<TupleType, ProjectionType, DelimiterType>&& Adapter)
{
    return JoinTupleByTo(Forward<TupleType>(Adapter.Tuple), MoveTemp(Adapter.Projection), Forward<DelimiterType>(Adapter.Delimiter), Builder);
}
 
} // UE::String::Private