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let arrayBuffer: WebAPI.FileAPI.file => Promise.t<ArrayBuffer.t>
let asBlob: WebAPI.FileAPI.file => WebAPI.FileAPI.blob
let bytes: WebAPI.FileAPI.file => Promise.t<array<int>>
let make: ( ~fileBits: array<WebAPI.FileAPI.blobPart>, ~fileName: string, ~options: WebAPI.FileAPI.filePropertyBag=?,) => WebAPI.FileAPI.file
let slice: ( WebAPI.FileAPI.file, ~start: int=?, ~end: int=?, ~contentType: string=?,) => WebAPI.FileAPI.blob
let stream: WebAPI.FileAPI.file => WebAPI.FileAPI.readableStream< array<int>,>
let text: WebAPI.FileAPI.file => Promise.t<string>