`CodeViewer`¶

Inspect bounded, escaped source text with optional language metadata.


Import	`from hedron import CodeViewer`
Distribution	`hedron`
Backend activity	No
Normal render mode	`RenderMode.FRAGMENT`

Live demo¶

from hedron import Text

Text("Hello, Hedron")

The preview is a local docs simulation (not a running Hedron server). Interactive demos show a “Simulated HTMX” trace when applicable.

Basic use¶

from hedron import CodeViewer

component = CodeViewer(config_text, language='toml', max_chars=20_000)

Compose under Page for full documents, or return from a fragment route for HTMX swaps.

How it works¶

CodeViewer truncates oversized content before rendering it in pre/code elements. It is an inspection surface, not an editor or executable sandbox.

This component's core behavior is server-rendered HTML and does not require a browser runtime. The preview is ordinary semantic HTML, so keyboard, form, link, and disclosure behavior comes from the platform.

Constructor and parameters¶

CodeViewer(code, *, language=None, max_chars=100_000)

Parameter	Type	Meaning
`code`	`str`	Source text.
`language`	`str \| None`	Language metadata.
`max_chars`	`int`	Hard display bound.

Composition and backend behavior¶

Keep CodeViewer at the smallest semantic boundary. Fragment routes should return only the replaced region and preserve stable target IDs across success, validation, empty, loading, and error responses.

This component is primarily presentational; keep any mutation on an explicit action or component route.

Accessibility¶

Provide context for what the code represents and keep horizontal scrolling keyboard-accessible.

Security¶

Escaping and SafeUrl / TrustedHtml are framework concerns; authorization and data exposure remain application code. Redact secrets before rendering.

Common mistakes¶

Redact secrets before construction; truncation is not redaction.
Do not copy docs-preview JavaScript into an application server.

Testing¶

from hedron import RenderMode, render

result = render(component, mode=RenderMode.FRAGMENT)
assert result.html
assert not result.diagnostics

All component demos · Built-in API · Testing

CodeViewer¶