Haha... yes, thanks. It was a mistake, I thought I did it too fast.
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The grammar:
expression = get | [ + | - ] term { ( + | - ) term }
term = factor { ( * | / ) factor }
factor = IDENTIFIER | VALUE | ( expression )
I can't make term parse, for instance 1 * 2 / 3
Indeed, the grammar does not admit 1*2/3 as a sentence of that
language although it
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 |
Why is Symbol = (String, Token)? A more sensible token type would
include values in the Value constructor and string identifiers in the
Identifier constructor; the strings in everything else seem redundant.
A more pure/monadic parser would have a type like this:
data Result a = Error String |
Why is Symbol = (String, Token)? A more sensible token type would
include values in the Value constructor and string identifiers in the
Identifier constructor; the strings in everything else seem redundant.
Surely you didn't read my original post, do you? I have a very limited
knowledge of
Surely you didn't read my original post, do you? I have a very limited
knowledge of Monad and I try to find a solution using my current skills
because the due date is within two weeks. Therefore, I don't think I can
create a Monadic parser for this.
I think you're giving up way too easily.
I hope you're right. 7 pages... 1-2 nights should be enough. Thanks for all.
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Hello,
2009/5/19 leledumbo leledumbo_c...@yahoo.co.id:
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 |
