Macro BOOST_VMD_IS_LIST_D

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## Macro BOOST_VMD_IS_LIST_D

BOOST_VMD_IS_LIST_D — Determines if a sequence is a Boost pplib list. Re-entrant version.

## Synopsis

    // In header: <boost/vmd/is_list.hpp>

    BOOST_VMD_IS_LIST_D(d, sequence)

## Description

The macro checks that the sequence is a pplib list. It returns 1 if it is a list, else if returns 0.

d = The next available BOOST_PP_WHILE iteration. sequence = input as a possible Boost PP list.

returns = 1 if it a list, else returns 0.

The macro will generate a preprocessing error if the input is in the form of a list but its end-of-list marker, instead of being an identifier, is a preprocessor token which VMD cannot parse, as in the example '(anything,&BOOST_PP_NIL)' which is a valid tuple but an invalid list.