codly.define-theme
Build a reusable theme dictionary by inheriting a built-in preset or another theme, then applying named token and element-setting overrides.
Signature
codly.define-theme(base: "thesis", ..overrides)base is named and defaults to "thesis"; overrides are named arguments. Positional arguments are not accepted.
Parameters
| Name | Type | Default | Meaning |
|---|---|---|---|
base |
str or dictionary |
"thesis" |
A preset name or an existing theme dictionary. The built-in names are thesis, dark, clean, github-light, solarized-light, and one-light. |
foreground |
paint or auto |
inherited | Text color for code; auto follows the surrounding text. |
muted |
paint or auto |
inherited | Muted text color, including line numbers; auto follows the resolved foreground. |
fill |
auto, paint or none, array of paints or none, or function |
inherited | Source-line fill. An array cycles by displayed row; a function receives a row dictionary with index, kind, source-line, and number. |
accent |
paint |
inherited | Main accent, including the language badge's default color and (unless explicitly overridden) the first highlight color. |
stroke |
stroke |
inherited | Default outline for code elements. |
radius |
length |
inherited | Default corner radius. |
inset |
length or dictionary |
inherited | Default code-line inset. |
header-fill, footer-fill, bubble-fill |
paint or none |
inherited | Backgrounds for the header, footer, and callout bubbles. |
syntax |
auto, str, path, or bytes |
inherited | TextMate plist theme for raw-code syntax highlighting. |
highlight-fill |
function |
inherited | Callback receiving a highlight color and returning its fill. |
highlight-colors |
paint or nonempty array of paints |
inherited | Default highlight color, or a palette cycled by highlights. |
language-colors |
bool |
inherited | Whether language badges use their language-specific colors. |
block, line, number, lang, file, header, footer, highlight, callout, bubble, annotation |
dictionary |
inherited | Overrides settable fields on the corresponding Codly element. The text entry in a section is a dictionary of native Typst text settings. |
All defaults are inherited from the selected base. Token names and section names are the complete supported top-level keys. Within a section, use fields supported by the corresponding Codly element. The fill callback’s row dictionary uses a zero-based displayed-row index; kind is code, skip, or callout, while source-line and number are none for generated rows or numbers that are not displayed.
Behavior
The result is a complete dictionary, not a show rule. It starts with the thesis defaults, merges a preset or dictionary base, then merges the named overrides. Section dictionaries merge one level deep, so separate fields such as header: (fill: red) and header: (align: left) can be combined when deriving a theme. Values inside those fields, including callbacks and nested dictionaries, are replaced as complete values.
An unknown preset or top-level key raises an error. Every section override must be a dictionary.
Pass the returned dictionary to codly.theme to render with it. Theme rules are scoped: explicit element fields and later local set rules can override theme values. Section text settings are applied as text settings to text within that element.
Example: Basic Usage
#import "@preview/codly:2.0.0" as codly
#let custom = codly.define-theme(
base: "thesis",
accent: accent,
header: (fill: accent.lighten(80%), align: left),
)
#show: codly.theme(custom)
#codly.new(
```py
return answer
```,
header: [Custom theme],
highlights: ((line: 1),),
)Edit & run on your device
The controls supply the example variables. Their definitions are hidden here; Copy code includes the current values and your edits.
