Generated-value resources

Import these factories from yidl.generation.data_def_sys (which reexports the owning matcher-value module). A matcher resource must satisfy the generated-value contract; a raw arbitrary object or raw composable is not interchangeable.

Factory	Accepted input / result	Evaluation
from_literal(value)	None, bool, int, float, complex, str; recursively tuple/list/dict/set	Rendered as Python literal source; other objects reject
from_astichi_code(source, ..., arg_names=..., keep_names=...)	String source and compile metadata	Dedented wrapper; lazy compile on to_generator()
from_import(module, name)	Dotted identifier module and identifier symbol	Import reference; composable conversion emits import surface
astichi_template(template, arg_names=..., bind=..., keep_names=...)	Generated-value template and optional generated-value edge expressions	Edge expressions evaluated against record

The public factory here is astichi_template; do not assume a from_astichi_template alias because an older plan used that phrase. The .yidl template resource lowers to this wrapper contract.

MatcherGeneratedValue stores source, file/line/offset, identifier mappings and keep names. Its first to_generator() lazily compiles and retains the unbound composable; later calls return it. This is neither a class cache nor memoization of a runtime callback.

Template edges

arg_names_for(record) expects a mapping of string keys and string identifier values. bind_for(record) expects a mapping with string keys. keep_names_for expects strings. Edge expressions are materialized, compiled as an expression, and evaluated with record in the local environment and normal Python builtins. They do not get an implicit arbitrary surrounding production namespace. Supply all required data explicitly; a missing provider is not repaired by a keep.

The canonical yidl_lark_v2_vertical.py example demonstrates generated resources, edge bindings and matcher-result production. Multi-record generic evaluated fields are a separate mechanism; the template edge API shown here receives one record object. A universal nested two-record edge environment is not qualified.

Use a fresh namespace/capture for callbacks, live types and opaque defaults. The factory's literal domain deliberately excludes arbitrary Python instances and bytes in this candidate. Preserve import provenance and do not invoke callbacks during generation to obtain something serializable.