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# app2

Basis Function Combinator

Like app1 with two items.

:   ... y x [Q] . app2
        -----------------------------------
        ... [y ...] [Q] . infra first
        [x ...] [Q]   infra first

Gentzen diagram.

## Definition

if not basis.

## Derivation

if not basis.

## Source

if basis

## Discussion

## Crosslinks