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Nested lambda capture in C ++

I have something like:

// think of Synonym as a set/vector of values
// the purpose of this function is to filter out elements from the 2 synonyms/sets,
// that are not related (similar to SQL inner join) - modifier modifies vars
void Clauses::modifies(Synonym& modifiers, Synonym& modifiedVars, UnaryPredicate isModifies) {
    // filter out any modifiers that does not modify (is related to) any of the variables in modifiedVar (left join)
    modifiers.removeIf([modifiedVars, &isModifies](int line) -> bool {
        return modifiedVars.none([line, &isModifies](int v) -> bool { 
            return isModifies(line, v);
        });
    });

    // filter out any candidate modifiedVars that is not modified by any modifiers (right join)
    modifiedVars.removeIf([modifiers, &isModifies](int varIndex) -> bool {
        return modifiers.none([varIndex, &isModifies](int line) -> bool {
            return isModifies(line, varIndex);
        });
    });

    // result is an something like an SQL inner join
}

The problem is that Visual Studio complains that:

Error   1   error C3480: 'PQL::Clauses::`anonymous-namespace'::<lambda1>::isModifies': a lambda capture variable must be from an enclosing function scope   h:\dropbox\sch\cs3202\spa_cpp\spa\pql.cpp   78
Error   2   error C2665: 'PQL::Clauses::`anonymous-namespace'::<lambda3>::<lambda3>' : none of the 2 overloads could convert all the argument types h:\dropbox\sch\cs3202\spa_cpp\spa\pql.cpp   78
...

Initially, the code did not pass predicates / conditions as links, but read somewhere, I thought I needed it, but it seems nothing changed

modifiers.removeIf([modifiedVars, isModifies] ...

UPDATE : I am using VS2010 for this project

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2 answers

If you use Visual Studio 2010, your code may cause an error that prevents you from committing a variable in a nested lambda.

Try using the default capture mode (for example, [&]) as a workaround.

This bug is fixed in VS2012.

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, Visual ++, GCC Clang . :

modifiedVars.removeIf([modifiers, &isModifies](int varIndex) -> bool {
    auto& isModifiesRedirect = isModifies;
    return modifiers.none([varIndex, &isModifiesRedirect ](int line) -> bool {
        return isModifiesRedirect (line, varIndex);
    });

. VS2010. VS2012. , Microsoft Connect , .

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