[erlang-questions] Are newlines significant in Erlang grammar?

Vlad Dumitrescu vladdu55@REDACTED
Tue Dec 20 18:46:02 CET 2011


On Tue, Dec 20, 2011 at 18:33, Ryan Molden <ryanmolden@REDACTED> wrote:
> Sure, but I was trying to avoid sprinking [\t\r\n ]* tokens everywhere
> throughout my grammar. My lexer currently ignores whitespace outside of
> comments and string literals and my parser works off the tokens my lexer
> produces.
> If what you are saying is correct it sounds like I can't do that, which
> means my parser's grammar explodes with tons of 'oh and there can be
> whitespace here, or needs to be whitespace here' kind of tokens :(

The issue here is that the dot is ambiguous and the rule is that a dot
followed by whitespace is the 'dot' token, while a dot followed
directly by an atom is an 'expr900' or more precisely a part of a
"packaged" atom. It is tricky that for example ".a .b .c" is a single
atom, ie whitespace is allowed before the dot but not after.
Personally I would vote for changing the package name separator (or
even remove the current package support, as it has been experimental
for many years and there are grave issues with it).


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