[jan@framey bug-repro]$ cat main.roc
app [main] { pf: platform "https://github.com/roc-lang/basic-cli/releases/download/0.17.0/lZFLstMUCUvd5bjnnpYromZJXkQUrdhbva4xdBInicE.tar.br" }

import pf.File
import pf.Stdout

main =
    File.readUtf8! "../input.txt"
    Stdout.line! "Hi."
[jan@framey bug-repro]$ roc check
roc: /lib64/libtinfo.so.6: no version information available (required by roc)

── TYPE MISMATCH in main.roc ───────────────────────────────────────────────────

Something is off with the body of this suffixed statement:

7│      File.readUtf8! "../input.txt"
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This File.readUtf8 call produces:

    Task Str […]

But a suffixed statement is expected to resolve to an empty record:

    Task {} […]

────────────────────────────────────────────────────────────────────────────────

1 error and 0 warnings found in 33 ms
[jan@framey bug-repro]$

[jan@framey bug-repro]$ cat main.roc
app [main] { pf: platform "https://github.com/roc-lang/basic-cli/releases/download/0.17.0/lZFLstMUCUvd5bjnnpYromZJXkQUrdhbva4xdBInicE.tar.br" }

import pf.File
import pf.Stdout

main =
    foo = File.readUtf8! "../input.txt"
    Stdout.line! "Hi."
[jan@framey bug-repro]$ roc check
roc: /lib64/libtinfo.so.6: no version information available (required by roc)

── UNUSED ARGUMENT in main.roc ─────────────────────────────────────────────────

This function doesn't use foo.

7│      foo = File.readUtf8! "../input.txt"
        ^^^

If you don't need foo, then you can just remove it. However, if you
really do need foo as an argument of this function, prefix it with an
underscore, like this: "_foo". Adding an underscore at the start of a
variable name is a way of saying that the variable is not used.

────────────────────────────────────────────────────────────────────────────────

0 errors and 1 warning found in 28 ms
[jan@framey bug-repro]$

[jan@framey bug-repro]$ cat main.roc
app [main] { pf: platform "https://github.com/roc-lang/basic-cli/releases/download/0.17.0/lZFLstMUCUvd5bjnnpYromZJXkQUrdhbva4xdBInicE.tar.br" }

import pf.File
import pf.Stdout

main =
    File.readUtf8! "../input.txt"
    |> Stdout.line!
[jan@framey bug-repro]$ roc check
roc: /lib64/libtinfo.so.6: no version information available (required by roc)
0 errors and 0 warnings found in 34 ms
[jan@framey bug-repro]$

jan@lenny:~/_roc/bug-repro$ cat main.roc
app [main] { pf: platform "../basic-cli/platform/main.roc" }

import pf.File
import pf.Stdout

main! = \{} ->
    File.readUtf8! "../input.txt"
    Stdout.line! "Hi."

jan@lenny:~/_roc/bug-repro$ roc dev

── UNRECOGNIZED NAME in ../basic-cli/platform/main.roc ─────────────────────────

The #UserApp module does not expose anything by the name 1.


── UNRECOGNIZED NAME in ../basic-cli/platform/main.roc ─────────────────────────

The #UserApp module does not expose anything by the name 1.


── IGNORED RESULT in main.roc ──────────────────────────────────────────────────

The result of this call to File.readUtf8! is ignored:

7│      File.readUtf8! "../input.txt"
        ^^^^^^^^^^^^^^

Standalone statements are required to produce an empty record, but the
type of this one is:

    Result Str [
        FileReadErr Path.Path InternalFile.ReadErr,
        FileReadUtf8Err Path.Path [BadUtf8 Utf8ByteProblem U64],
    ]

If you still want to ignore it, assign it to _, like this:

    _ = File.delete! "data.json"


── MISSING DEFINITION in main.roc ──────────────────────────────────────────────

main is listed as exposed, but it isn't defined in this module.

You can fix this by adding a definition for main, or by removing it
from exposes.

────────────────────────────────────────────────────────────────────────────────

4 errors and 1 warning found in 44 ms
.

You can run the program anyway with roc run
jan@lenny:~/_roc/bug-repro$