til/deno/read-in-the-contents-of-a-file.md

Read In The Contents Of A File

Deno offers some nice utilities out of the box like reading in the contents of a file from the filesystem. The readTextFile function is available on the Deno object.

// Read a file using Deno
const text: string = await Deno.readTextFile("./first_input.txt");

You use a top-level await with the function call and, assuming the file exists, it will read the contents in. In this case, I assign them to the text variable.

For the file reading to work when the program is executed, you must use the --allow-read flag.

$ deno run --allow-read program.ts

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