# `Schooner.Compiled`
[🔗](https://github.com/ausimian/schooner/blob/1.0.0/lib/schooner/compiled.ex#L1)

Opaque artifact produced by `Schooner.compile/2` and consumed by
`Schooner.run_compiled/2`.

A `%Compiled{}` holds the **post-expansion core AST** of a program
together with the **runtime variable bindings** that the program's
`(import ...)` declarations resolved to at compile time. Macros are
already gone from the AST — `let`, `cond`, `when`, `case`, etc.
have been rewritten into `quote` / `if` / `lambda` / `define` /
`define-values` / `begin` / `letrec*` / `quasiquote` / application
/ variable references.

## Reuse semantics

The same `%Compiled{}` can be passed to `Schooner.run_compiled/2`
many times against many `Schooner.Environment`s — that is the
embedding cache win. The captured `var_bindings` are re-applied
to the runtime env on every call; macros expanded at compile
time stay expanded.

Compatibility constraint: a compiled program is valid against
any environment whose **macro environment is compatible** with
the registry passed to `compile`. Variable sets can differ
freely — host primitives can be swapped, and the compiled
program's `(import ...)` bindings are baked in so they shadow
any same-named runtime overrides. Macro additions made *after*
compile (via a different `Environment` at run time) will not
re-expand the program.

## Opacity

Embedders must treat the struct as opaque — pattern-matching on
internals is unsupported and reserved for evaluator changes
(the v2.0 evaluator rewrite is the seam this opacity protects).

# `t`

```elixir
@opaque t()
```

---

*Consult [api-reference.md](api-reference.md) for complete listing*