[Libraries]

Libraries

Abstract

TradingView libraries publish as namespace/Name/version with exported members. PYNE implements an in-process analogue: evaluate a library("Title") script (or register source by path), collect exports (export const, exported functions, types), then import binds an alias to a LibraryModule for alias.member access. There is no network publish step—the registry is the host’s responsibility.

Conceptual model

Interface surface

Library script

//@version=5
library("MyMath")

export add(float a, float b) =>
    a + b

export const float PHI = 1.6180339887

On script completion, StatementEvaluator finalizes _pending_library_exports onto the active LibraryModule and calls LibraryRegistry.register.

Consumer import

//@version=5
indicator("use")
import user/MyMath/1 as M
plot(M.add(close, M.PHI))

Resolution (LibraryRegistry.lookup):

1. Exact (namespace, name, version) if provided and registered.
2. Else title-only match (MyMath) for local evaluation workflows without publisher path.

API on the evaluator

ev.register_library_source(namespace, name, version, source_str)
mod = ev.lookup_library(namespace=..., name=..., version=...)

register_library_source stores Pine text for lazy load on import; evaluating a library script eagerly populates exports.

LibraryModule

Dataclass with title, optional namespace/version, and exports: dict[str, Any]. Attribute access reads exports; missing members raise AttributeError with a clear message. NameEvaluator routes alias.member when the base value is a LibraryModule.

Internals

Exportable values include callables (user functions), constants, and type-related bindings depending on declaration paths. Exported methods participate in the same call machinery as local functions once retrieved from the module.

Invariants & edge cases

1. Evaluate library before consumer (or register source for lazy import). Empty registry → import failure.
2. Same evaluator instance (or shared registry) must see both scripts—registries are not process-global unless the host shares them.
3. Version is part of the path key. Mismatched version does not fall back to another version automatically when namespace is specified.
4. Title registration always updates _by_title so simple local titles work without publisher metadata.
5. No TV account auth. Publishing/versioning outside the process is out of scope.

Worked examples

Explicit registration

from pynescript.ast.evaluator import NodeLiteralEvaluator

ev = NodeLiteralEvaluator()
ev.evaluate_script(library_source)   # registers by title
ev.evaluate_script(consumer_source)  # import by title or path

Path registration without pre-eval

ev.register_library_source("user", "MyMath", 1, library_source)
# import user/MyMath/1 loads and evaluates source on demand

Failure modes

See also

• Expressions & statements
• Builtins declarations
• End-user library API guide