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docs/api/color-support-label.md

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+---
+name: color-support-label
+group: api
+category: formatter
+update-time: 20260520
+description: Convert a ColorSupport value into its stable string label.
+key-word:
+    - color
+    - formatter
+    - label
+    - public
+---
+
+## Color-support-label
+
+Convert `ColorSupport` into its stable string label. This helper is useful for diagnostics, tests, and config-oriented output that should mirror the built-in color support names.
+
+### Interface
+
+```moonbit
+pub fn color_support_label(support : ColorSupport) -> String {
+```
+
+#### input
+
+- `support : ColorSupport` - Color support enum value to label.
+
+#### output
+
+- `String` - Stable label such as `basic` or `truecolor`.
+
+### Explanation
+
+Detailed rules explaining key parameters and behaviors
+
+- The returned strings are stable enum labels used by config and tests.
+- This helper is presentation-oriented and does not change formatter behavior by itself.
+- It is useful when code should display or assert a readable color support mode.
+
+### How to Use
+
+Here are some specific examples provided.
+
+#### When Need A Readable Color Support Name
+
+When diagnostics or tests should show the selected color capability:
+```moonbit
+let label = color_support_label(ColorSupport::Basic)
+```
+
+In this example, `label` becomes `"basic"`.
+
+### Error Case
+
+e.g.:
+- There is no failure path for valid `ColorSupport` values.
+
+- If code needs to choose rendering behavior, the enum value itself is usually more useful than its label string.
+
+### Notes
+
+1. This helper is mostly useful for readable output and assertions.
+
+2. It pairs naturally with config parsing and formatter inspection tests.