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ConstructDDIs[expr] constructs all scalar dimensional dependent identities that can be build out of expr. |

ConstructDDIs[expr, frees] constructs all dimensional dependent identities that can be build out of expr and that have free indices frees. |

ConstructDDIs[expr, frees, sym] constructs all dimensional dependent identities that can be build out of expr and that have the symmetry sym imposed on their free indices frees. |

- ConstructDDIs returns a list of tensorial expressions that are zero due to over-antisymmetrization.

- ConstructDDIs uses AllContractions internally, hence its conditions on the input expression also apply to ConstructDDIs.

- The number of indices of expr plus the number of additional frees has to be at least , where is the dimension of the manifold.

- ConstructDDIs computes all possible contractions between expr and the basic dimensional dependent identity, BasicDDI.

- ConstructDDIs defines the BasicDDI the first time it's called.

- ConstructDDIs only works when the dimension of the manifold is a non-generic integer.

- It is possible to change the dimension of the manifold in between ConstructDDIs calls.