Module ast 

The loose syntax tree, one step away from the grammar.

This mirrors what was written, not what it means: no types are resolved, no names are mapped, no relation has two sides yet. Lowering turns it into the strict IR.

The separation is not ceremony. Relation resolution needs the complete set of models, which does not exist part-way through a parse, so an IR built directly in the parse walk would be wrong for any schema that references a model before declaring it — which is most of them.

Structs

Ast

A parsed schema file.

Attr

An @attr or @@attr, with its arguments.

Block

A datasource or generator block.

ConfigEntry

One key = value line inside a block.

EnumDecl

An enum declaration.

FieldDecl

A field within a ModelDecl.

ModelDecl

A model declaration.

VariantDecl

One variant of an EnumDecl.

Enums

Arg

One argument of an Attr.

Arity

How many values a field holds.

Decl

One top-level declaration.

Value

A value written in an attribute argument or a config entry.