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unfused_lvalue_args

Description

An n-ary Polymorphic Function Object adapter template for an unary Polymorphic Function Object target function. When called, its arguments are bundled to a Random Access Sequence of references that is passed to the target function object. Only LValue arguments are accepted.

The type of the target function is allowed to be const qualified or a reference. Const qualification is preserved and propagated appropriately (in other words, only const versions of operator() can be used if the target function object is const - or, in case the target function object is held by value, the adapter is const).

/functional/adapter/unfused_lvalue_args.hpp>

Synopsis
template <class Function>
class unfused_lvalue_args;
Template parameters

Parameter

Description

Default

Function

A unary Polymorphic Function Object

Model of

Notation

F

A possibly const qualified, unary Polymorphic Function Object type or reference type thereof

f

An object convertible to F

UL

The type unfused_lvalue_args<F>

ul

An instance of UL, initialized with f

a0...aN

Arguments to ul

Expression Semantics

Expression

Semantics

UL(f)

Creates a fused function as described above, initializes the target function with f.

UL()

Creates a fused function as described above, attempts to use F's default constructor.

ul(a0...aN)

Calls f with a Sequence that contains references to the arguments a0...aN.

Example
struct fused_incrementer
{
    template <class Seq>
    struct result
    {
        typedef void type;
    };

    template <class Seq>
    void operator()(Seq const & s) const
    {
        for_each(s,++boost::lambda::_1);
    }
};

void try_it()
{
    unfused_lvalue_args<fused_incrementer> increment;
    int a = 2; char b = 'X';
    increment(a,b);
    assert(a == 3 && b == 'Y');
}
See also

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