topmark.filetypes.checks ¶

Insert-checker utilities for TopMark file types.

This package provides file-type specific checks (InsertChecker instances) that determine whether a TopMark header can be safely inserted into a given file.

Unlike content matchers (see topmark.filetypes.detectors), which classify a file's type by examining its content, insert checkers focus on pre-insert eligibility. For example, a checker may forbid inserting a header into a JSON file that is actually JSON without comments, or into an XML document missing a declaration.

Responsibilities

Expose reusable, file-type specific InsertChecker callables.
Encapsulate constraints that go beyond syntax (e.g., semantic restrictions).
Surface advisory reasons when insertion is not supported.

Relationship

topmark.filetypes.model defines the InsertChecker protocol and the FileType dataclass property where these checkers can be attached.
topmark.filetypes.detectors provides complementary content matchers for file type detection.