Lexer not parsing lambda correctly when directly followed by identifier

gdupont1 / rodin-hs

A collection of Haskell modules for handling Rodin files

GNU General Public License v3.0

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Lexer not parsing lambda correctly when directly followed by identifier #1

Closed gdupont1 closed 3 years ago

gdupont1 commented 3 years ago

When the character lambda (λ) is followed directly by an identifier, the lexer does not recognize it as a separate token, leading to incorrect reading of strings such as (λx . ...) (not parsed as a lambda expression then).

gdupont1 commented 3 years ago

This was caused by our use of Data.Char.isAlpha; since it bases itself on Unicode categories, it appears that Data.Char.isAlpha 'λ' returns True.

This has been changed and fixed, hopefully.

(fixed in commit #1163794b91970ea99979049543510dd3360cde18)