30 lines
642 B
JavaScript
30 lines
642 B
JavaScript
/**
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* test handling of const params
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* - reassignment prohibited
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* - durable refinements
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*
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* Currently gated in .flowconfig:
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*
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* [options]
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* experimental.const_params
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*
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* Syntax to follow
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*
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* @flow
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*/
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function cannot_reassign(x: string) {
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x = "hey"; // error, const param cannot be reassigned
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}
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// Note: const params use the same machinery as explicit
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// const bindings, which are tested more extensively elsewhere.
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// Here we're just making sure the machinery is hooked up.
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//
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function durable_refi(x: ?number) {
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if (x) {
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// ok: if x is truthy here, it's truthy everywhere
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return () => { var y:number = x; };
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}
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}
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