E0310: optional parameter cannot have both '?' and initializer; remove '?'

In TypeScript, parameters can be explicitly marked as optional with ?. It is a syntax error to write a default initializer for a parameter marked optional with ?:

async function download(uri, options? = {}) {
  /* ... */
}

Parameters with default initializers are always optional. To fix this syntax error, remove the redundant ?:

async function download(uri, options = {}) {
  /* ... */
}

Introduced in quick-lint-js version 2.10.0.

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