Syntax error with ->

[hissssst]

Environment

$ uname -a
Linux 5.13.11 #1-NixOS SMP Sun Aug 15 12:01:57 UTC 2021 x86_64 GNU/Linux

$ elixir --version
Erlang/OTP 24 [erts-12.0.3] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [jit]

Elixir 1.12.2 (compiled with Erlang/OTP 24)

Current behavior

See https://elixirforum.com/t/does-this-worth-an-issue/41897/4 for examples

The main problem here is that

f(1 -> 2)

results in a syntax error

But something like

(1 -> 2) |> f()
# or
f((1 -> 2))

Is a valid expression

Expected behavior

f(1 -> 2)

Does not result in syntax error

[josevalim]

This is intentional. In this case, the parentheses are delimiters of the ->. In the same way that fn/end and do/end are. Or in the same way [ and ] are delimiters around a list. So you do need to write f((1 -> 2)). Note this is mostly used in typespecs.