E0262: leading commas are not allowed in generic parameter lists

In a TypeScript generic class, function, or type alias, the generic parameter list is a comma-separated list of variables surrounded by < and >. It is a syntax error for the parameter list to start with an extra comma:

class MagicMap<
    , Key
    , Value
    > {
  // ...
}

To fix this error, remove the leading ,:

class MagicMap
    < Key
    , Value
    > {
  // ...
}

Introduced in quick-lint-js version 2.8.0.

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