Compiler error produces unexpected output when rendered in a terminal about compiler HOT 3 OPEN

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from compiler.

As far as I can tell, “breaks terminal rendering” is a bit of a red herring. What seems to happen is that line 6 of the error message contains 65532 spaces in a row. Terminals wrap long lines, which in effect results in a very long empty section to scroll through in the middle of the error message.

Here I replaced long sequences of a character like XXXXXXX… with {X}*42:

❯ elm make Main.elm 2> output.txt
Detected problems in 1 module.

❯ node -p 'fs.readFileSync("output.txt", "utf8").replace(/(.)\\1{5,}/g, m => `{${m[0]}}*${m.length}`)'
-- NAME CLASH {-}*57 Main.elm

This `case` pattern has multiple `a` variables.

6|{ }*9[ a, a ] -> list
{ }*16^{ }*65532^
How can I know which one you want? Rename one of them!

Random note: 65532 is suspiciously close to 2^16 = 65,536.

from compiler.

As far as I can tell, “breaks terminal rendering” is a bit of a red herring.

You're right. That was probably some unfortunate wording on my part. I've updated the description accordingly. 🙂

from compiler.