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docs/api/style-markup-mode-label.md

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+---
+name: style-markup-mode-label
+group: api
+category: formatter
+update-time: 20260520
+description: Convert a StyleMarkupMode value into its stable string label.
+key-word:
+    - style
+    - formatter
+    - label
+    - public
+---
+
+## Style-markup-mode-label
+
+Convert `StyleMarkupMode` into its stable string label. This helper is useful for diagnostics, tests, and config inspection output.
+
+### Interface
+
+```moonbit
+pub fn style_markup_mode_label(mode : StyleMarkupMode) -> String {
+```
+
+#### input
+
+- `mode : StyleMarkupMode` - Markup mode enum value to label.
+
+#### output
+
+- `String` - Stable label such as `disabled`, `builtin`, or `full`.
+
+### Explanation
+
+Detailed rules explaining key parameters and behaviors
+
+- The returned strings match the built-in markup mode vocabulary.
+- This helper is presentation-oriented and does not change formatting behavior by itself.
+- It is especially useful when tests or logs should expose the active markup policy clearly.
+
+### How to Use
+
+Here are some specific examples provided.
+
+#### When Need A Readable Markup Mode Name
+
+When diagnostics should show which markup mode is active:
+```moonbit
+let label = style_markup_mode_label(StyleMarkupMode::Builtin)
+```
+
+In this example, `label` becomes `"builtin"`.
+
+### Error Case
+
+e.g.:
+- There is no failure path for valid `StyleMarkupMode` values.
+
+- If code needs behavior rather than display text, the enum value itself is usually more useful than the returned label.
+
+### Notes
+
+1. This helper is mainly useful for human-readable inspection and assertions.
+
+2. It pairs naturally with formatter config tests and debug output.