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chemigram.core.binding

chemigram.core.binding

L1 vocabulary binding via EXIF lookup.

Per RFC-015 → ADR-053, takes :class:~chemigram.core.exif.ExifData plus a :class:VocabularyIndex lookup and returns L1 entries matching (make, model, lens_model) exactly. No fuzzy matching, no normalization, no focal-length awareness.

The "exact-match only" rule is intentional. Per ADR-016, L1 is empty by default — the typical case is "no L1 entries match" and :func:bind_l1 returns an empty list. Photographers add L1 entries keyed to their actual gear; fuzzy matching would silently introduce ambiguity into a photographer-curated, intentionally narrow space.

Public API
  • :class:VocabularyIndex — Protocol the vocabulary system implements
  • :func:bind_l1 — pure resolution function

VocabularyIndex

Bases: Protocol

Minimal interface :func:bind_l1 needs from the vocabulary system.

The full vocabulary index lands in a later issue; this Protocol is enough to test :func:bind_l1 with a fake.

lookup_l1 

lookup_l1(make, model, lens_model)

Return L1 entries that exactly match the camera+lens identity.

Returns [] if no entries match. Empty is the expected default per ADR-016 (L1 is empty until photographer authors entries) — callers must not treat empty as an error.

Source code in src/chemigram/core/binding.py 
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def lookup_l1(
    self,
    make: str,
    model: str,
    lens_model: str,
) -> list[DtstyleEntry]:
    """Return L1 entries that exactly match the camera+lens identity.

    Returns ``[]`` if no entries match. Empty is the expected
    default per ADR-016 (L1 is empty until photographer authors
    entries) — callers must not treat empty as an error.
    """
    ...

bind_l1 

bind_l1(exif, vocabulary)

Resolve L1 entries for a raw's camera+lens identity.

v1 rule (RFC-015 / ADR-053): exact match on (exif.make, exif.model, exif.lens_model). Returns [] if no entry matches — common case during Phase 1 since the OSS starter pack has no L1 entries (ADR-016).

Pure: no I/O, no mutation. The match logic lives in :meth:VocabularyIndex.lookup_l1; this function is the type-checked binding-call boundary.

Source code in src/chemigram/core/binding.py 
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def bind_l1(exif: ExifData, vocabulary: VocabularyIndex) -> list[DtstyleEntry]:
    """Resolve L1 entries for a raw's camera+lens identity.

    v1 rule (RFC-015 / ADR-053): exact match on
    ``(exif.make, exif.model, exif.lens_model)``. Returns ``[]`` if no
    entry matches — common case during Phase 1 since the OSS starter
    pack has no L1 entries (ADR-016).

    Pure: no I/O, no mutation. The match logic lives in
    :meth:`VocabularyIndex.lookup_l1`; this function is the
    type-checked binding-call boundary.
    """
    return vocabulary.lookup_l1(exif.make, exif.model, exif.lens_model)