CodeHighlight.svelte

The source code to syntax highlight.

Language identifier (e.g., 'ts', 'css', 'html', 'json', 'svelte', 'md').

Purpose: - When grammar is not provided, used to look up the grammar via syntax_styler.get_lang(lang) - Used for metadata: sets the data-lang attribute and determines language_supported

Special values: - null - Explicitly disables syntax highlighting (content rendered as plain text) - undefined - Falls back to default ('svelte')

Relationship with grammar: - If both lang and grammar are provided, grammar takes precedence for tokenization - However, lang is still used for the data-lang attribute and language detection

Highlighting mode for this component.

Options: - 'auto' - Uses CSS Custom Highlight API if supported, falls back to HTML mode - 'ranges' - Forces CSS Custom Highlight API (requires browser support) - 'html' - Forces HTML generation with CSS classes

Note: CSS Custom Highlight API has limitations and limited browser support. Requires importing theme_highlight.css instead of theme.css.

Optional custom grammar object for syntax tokenization.

When to use: - To provide a custom language definition not registered in syntax_styler.langs - To use a modified/extended version of an existing grammar - For one-off grammar variations without registering globally

Behavior: - When provided, this grammar is used for tokenization instead of looking up via lang - Enables highlighting even if lang is not in the registry (useful for custom languages) - The lang parameter is still used for metadata (data-lang attribute) - When undefined, the grammar is automatically looked up via syntax_styler.get_lang(lang)

Whether to render as inline code or block code. Controls display via CSS classes.

Whether to wrap long lines in block code. Sets white-space: pre-wrap instead of white-space: pre.

Behavior: - Wraps at whitespace (spaces, newlines) - Long tokens without spaces (URLs, hashes) will still scroll horizontally - Default false provides traditional code block behavior

Only affects block code (ignored for inline mode).

Custom SyntaxStyler instance to use for highlighting. Allows using a different styler with custom grammars or configuration.

Optional snippet to customize how the highlighted markup is rendered. - In HTML mode: receives the generated HTML string - In range mode: receives the plain text content