SOURCE

match l {
    [] -> Err(EmptyList)
    [.., e] -> Ok(e)
}

EXPECTED

PARSE ERROR - wrong_arrow.md:2:8:2:8 PARSE ERROR - wrong_arrow.md:3:13:3:13 UNDEFINED VARIABLE - wrong_arrow.md:1:7:1:8

PROBLEMS

PARSE ERROR Match branches use => instead of ->.

wrong_arrow.md:2:8:2:8:

    [] -> Err(EmptyList)

PARSE ERROR Match branches use => instead of ->.

wrong_arrow.md:3:13:3:13:

    [.., e] -> Ok(e)

UNDEFINED VARIABLE Nothing is named l in this scope. Is there an import or exposing missing up-top?

wrong_arrow.md:1:7:1:8:

match l {

TOKENS

KwMatch,LowerIdent,OpenCurly,
OpenSquare,CloseSquare,OpArrow,UpperIdent,NoSpaceOpenRound,UpperIdent,CloseRound,
OpenSquare,DoubleDot,Comma,LowerIdent,CloseSquare,OpArrow,UpperIdent,NoSpaceOpenRound,LowerIdent,CloseRound,
CloseCurly,
EndOfFile,

PARSE

(e-match
	(e-ident (raw "l"))
	(branches
		(branch
			(p-list)
			(e-apply
				(e-tag (raw "Err"))
				(e-tag (raw "EmptyList"))))
		(branch
			(p-list
				(p-list-rest)
				(p-ident (raw "e")))
			(e-apply
				(e-tag (raw "Ok"))
				(e-ident (raw "e"))))))

FORMATTED

match l {
	[] => Err(EmptyList)
	[.., e] => Ok(e)
}

CANONICALIZE

(e-match
	(match
		(cond
			(e-runtime-error (tag "ident_not_in_scope")))
		(branches
			(branch
				(patterns
					(pattern (degenerate false)
						(p-list
							(patterns))))
				(value
					(e-tag (name "Err")
						(args
							(e-tag (name "EmptyList"))))))
			(branch
				(patterns
					(pattern (degenerate false)
						(p-list
							(patterns
								(p-assign (ident "e")))
							(rest-at (index 0)))))
				(value
					(e-tag (name "Ok")
						(args
							(e-lookup-local
								(p-assign (ident "e"))))))))))

TYPES

(expr (type "[Err([EmptyList, .._others]), Ok(_a), .._others2]"))

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