# Bind lambda spells

**🟡 Intermediate · Lesson 12**

Even a lambda is a spell - it MUST carry a binding_name (the law the runtime enforces); melds address it by (frame, name) because binding_name alone is never an address. Callable = unique.

## Before you run

Use the [Intermediate guide](../../intermediate/index.md) for prerequisite concepts. Run from a checkout with Melder installed and Python 3.14 free-threading selected. The collection download includes the level's local helper modules.

## Run the saved script

```bash
python UX_and_AIX_experiences/02_intermediate/12_bind_lambda_spells.py
```

```powershell
py -3.14t UX_and_AIX_experiences/02_intermediate/12_bind_lambda_spells.py
```

{download}`Download this collection <../../downloads/intermediate-examples.zip>` · [Source on GitHub](https://github.com/Synaptic724/melder/blob/a30a754d0bb61db0b142936010cdb82cffecec6f/UX_and_AIX_experiences/02_intermediate/12_bind_lambda_spells.py)

## Public surface

bind(spell=<lambda>), binding_name, callable-unique law

## Code

```{literalinclude} ../../downloads/02_intermediate/12_bind_lambda_spells.py
:language: python
:linenos:
```

## Check the outcome

The script contains its own assertions or demonstrated refusal paths. Run it to evaluate those checks against your installed version. The code above is taken directly from the saved file; no run output is invented here.

[More intermediate examples](index.md) · [Level guide](../../intermediate/index.md)

## Related guides

- [Fluent registration](../../intermediate/registration.md)