[Haskell-cafe] Expression parsing problem

[leledumbo]

> Indeed, the grammar does not admit "1*2/3" as a sentence ...

Huh? Why not? "1 * 2 / 3" should match factor "*" factor "/" factor.
Remember that { } is repetition, so it should be able to handle such term.

> expression ::= term | term "+" expression
> term ::= factor | factor "*" term
> factor ::= constant | variable | "(" expression ")" 

Oh, left recursion. Well, it should be easy to transform:

expression ::= term | moreTerm
term ::= factor | moreFactor
moreTerm ::= term "+" expression
factor ::= constant | variable | "(" expression ")" 
moreFactor := factor "*" term

correct?
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