Delimiters helpers which work with ostream helpers.

IOStreams/delimiters.h

@@ -0,0 +1,138 @@
+static_assert( __cplusplus > 2020'00 );
+
+#pragma once
+
+#include <Alepha/Alepha.h>
+
+#include <ios>
+#include <ostream>
+#include <optional>
+
+#include <Alepha/StaticValue.h>
+
+namespace Alepha::Hydrogen::IOStreams  ::detail::  delimiters
+{
+	inline namespace exports
+	{
+		enum { FieldDelimiter };
+		enum { RecordDelimiter };
+	}
+
+	namespace C
+	{
+		const char defaultFieldDelimiter= '\t';
+		const char defaultRecordDelimiter= '\n';
+	}
+
+	namespace storage
+	{
+		inline StaticValue< std::optional< char > > globalFieldDelimiter;
+		inline StaticValue< std::optional< char > > globalRecordDelimiter;
+	}
+
+	inline char
+	globalFieldDelimiter()
+	{
+		if( not storage::globalFieldDelimiter().has_value() ) storage::globalFieldDelimiter()= C::defaultFieldDelimiter;
+		return storage::globalFieldDelimiter().value();
+	}
+
+	inline char
+	globalRecordDelimiter()
+	{
+		if( not storage::globalRecordDelimiter().has_value() ) storage::globalRecordDelimiter()= C::defaultRecordDelimiter;
+		return storage::globalRecordDelimiter().value();
+	}
+	
+
+	inline const int fieldIndex= std::ios::xalloc();
+
+	inline void
+	setFieldDelimiterOnIOS( std::ios &ios, const char ch )
+	{
+		ios.iword( fieldIndex )= ch;
+	}
+
+	inline char
+	getFieldDelimiter( std::ios &ios )
+	{
+		if( ios.iword( fieldIndex ) == 0 ) setFieldDelimiterOnIOS( ios, globalFieldDelimiter() );
+
+		return ios.iword( fieldIndex );
+	}
+
+	inline std::ostream &
+	operator << ( std::ostream &os, decltype( FieldDelimiter ) )
+	{
+		return os << getFieldDelimiter( os );
+	}
+
+	struct FieldDelimiterSetter
+	{
+		const char ch;
+
+		friend std::ostream &
+		operator << ( std::ostream &os, const FieldDelimiterSetter &s )
+		{
+			setFieldDelimiterOnIOS( os, s.ch );
+			return os;
+		}
+	};
+
+	namespace exports
+	{
+		auto
+		setFieldDelimiter( const char ch )
+		{
+			return FieldDelimiterSetter{ ch };
+		}
+	}
+
+	inline const int recordIndex= std::ios::xalloc();
+
+	inline void
+	setRecordDelimiterOnIOS( std::ios &ios, const char ch )
+	{
+		ios.iword( recordIndex )= ch;
+	}
+
+	inline char
+	getRecordDelimiter( std::ios &ios )
+	{
+		if( ios.iword( recordIndex ) == 0 ) setRecordDelimiterOnIOS( ios, globalRecordDelimiter() );
+
+		return ios.iword( recordIndex );
+	}
+
+	inline std::ostream &
+	operator << ( std::ostream &os, decltype( RecordDelimiter ) )
+	{
+		return os << getRecordDelimiter( os );
+	}
+
+	struct RecordDelimiterSetter
+	{
+		const char ch;
+
+		friend std::ostream &
+		operator << ( std::ostream &os, const RecordDelimiterSetter &s )
+		{
+			setRecordDelimiterOnIOS( os, s.ch );
+			return os;
+		}
+	};
+
+	namespace exports
+	{
+		auto
+		setRecordDelimiter( const char ch )
+		{
+			return RecordDelimiterSetter{ ch };
+		}
+	}
+}
+
+namespace Alepha::Hydrogen::IOStreams::inline exports::inline delimiters
+{
+	using namespace detail::delimiters::exports;
+}