Function isCmcdEventKey

isCmcdEventKey(
    key: string,
): key is
    | "url"
    | "e"
    | "h"
    | (keyof CmcdRequest)
    | "cmsdd"
    | "cmsds"
    | "rc"
    | "smrt"
    | "ttfb"
    | "ttfbb"
    | "ttlb"
    | "cen"
    | "ts"
Check if a key is a valid CMCD event key.
Parameters
- key: string
  The key to check.
Returns key is
    | "url"
    | "e"
    | "h"
    | (keyof CmcdRequest)
    | "cmsdd"
    | "cmsds"
    | "rc"
    | "smrt"
    | "ttfb"
    | "ttfbb"
    | "ttlb"
    | "cen"
    | "ts"
true if the key is a valid CMCD event key, false otherwise.
Example
```
equal(isCmcdEventKey('e'), true)
equal(isCmcdEventKey('cmsdd'), true)
```
- Defined in isCmcdEventKey.ts:20