# map_transfer · FT4 Rell API · Chromia Docs (concept)

> function map_ transfer(init_ tx_ rid: byte_ array, init_ op_ index: integer, transaction_ rid: byte_ array, op_ index: integer): (init_ tx_ rid: byte_ arra

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.crosschain/map_transfer/

FUNCTION

# map\_transfer

```signature
function map_transfer(init_tx_rid: byte_array, init_op_index: integer, transaction_rid: byte_array, op_index: integer): (init_tx_rid: byte_array, init_op_index: integer, transaction_rid: byte_array?, op_index: integer?)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/core/crosschain/mappers.rell#lines-33)

Maps a transfer's init\_tx\_rid and init\_op\_index into a readable format for the frontend.

**Parameters**

* **init\_tx\_rid** — the init\_tx\_rid to retrieve
* **init\_op\_index** — the init\_op\_index to retrieve

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.core.crosschain/map_transfer.html)Generated API reference, mirrored from the live docs