# tx.op · Rell standard library · Chromia Docs (concept)

> function op(ops: list < op >): tx Add a list of test operation calls to this test transaction builder. Parameters ops — the list of operations to add Since

Source: https://docs.chromia.com/pages/rell-stdlib/-rell-system-library/rell.test/tx/op/

FUNCTION

# tx.op

```signature
function op(ops: list<op>): tx
```

Add a list of test operation calls to this test transaction builder.

**Parameters**

* **ops** — the list of operations to add

Since 0.10.4

---

```signature
function op(ops: op...): tx
```

Add test operation calls to this test transaction builder.

**Parameters**

* **ops** — the operations to add

Since 0.10.4

---

```signature
function op(ops: list<-mirror_struct<-operation>>): tx
```

Add a list of test operation calls to this test transaction builder.

The test operation calls are given as `struct<operation>` values.

For example, calls to the operation:

Rell

```
operation my_op(foo: integer, bar: list<text>) { ... }
```

may be passed as a `struct<my_op>`:

Rell

```
my_transaction_builder.op([
    struct<my_op>(foo = 1, bar = ["a", "b"]),
    struct<my_op>(foo = 2, bar = ["c", "d"])
]);
```

**Parameters**

* **ops** — the list of test operation calls to add to this transaction builder

Since 0.10.4

---

```signature
function op(ops: mirror_struct<-operation>...): tx
```

Add the given test operation calls to this test transaction builder.

The test operation calls are given as `struct<operation>` values.

For example, calls to the operation:

Rell

```
operation my_op(foo: integer, bar: list<text>) { ... }
```

may be passed as a `struct<my_op>`:

Rell

```
my_transaction_builder.op(
    struct<my_op>(foo = 1, bar = ["a", "b"]),
    struct<my_op>(foo = 2, bar = ["c", "d"])
);
```

**Parameters**

* **ops** — the test operation calls to add to this transaction builder

Since 0.10.4

[View this page on docs.chromia.com](https://docs.chromia.com/pages/rell-stdlib/-rell%20-system%20-library/rell.test/tx/op.html)Generated API reference, mirrored from the live docs