EBNF grammar not recognizing end of file correctly

[Matej Zabsky]

Hello,

I'm trying to make a CSS parser using ETO Parse. So far I have mostly just translated parts of the official CSS grammar to the W3C EBNF notation supported by Eto - you can see the grammar on GitHub (also the invocation of Eto.Parse and a test case that can run the whole thing). It is nowhere near finished, but it should be able to parse a simple CSS file.

However when I run the test case on a simple string: "div#hash{background:red;}     #someid{padding:1px 1px;}", it returns a GrammarMatch with this ErrorMessage:

Index=57, Context="px 1px;}>>>"
Expected:
S: Repeat: Unary: Alternative
ident: Sequence
element_name: Alternative
hash: Sequence
class: Sequence
attrib: Sequence
pseudo: Sequence
ruleset: Sequence

Suprisingly, Match.Success is true, but I don't believe I should ignore the message. When I print the syntax tree as contained in the match, I get a tree which seems to be correct:

stylesheet - div#hash{background:red;}     #someid{padding:1px 1px;}

ruleset - div#hash{background:red;}     

selectors - div#hash

selector - div#hash

element_name - div

ident - div

hash - #hash

ident - hash

declarations - background:red;

declaration - background:red

ident - background

expression - red

term - red

ident - red

S -      

ruleset - #someid{padding:1px 1px;}

selectors - #someid

selector - #someid

hash - #someid

ident - someid

declarations - padding:1px 1px;

declaration - padding:1px 1px

ident - padding

expression - 1px 1px

term - 1px

number - 1px

operator -  

S -  

term - 1px

number - 1px

As far as I can tell, the grammar should terminate the match correctly - the top level "stylesheet ::= (ruleset)*" is as simple as it gets and from the error message provided by Eto, it look like it expects another ruleset. I tried adding a newline to the end of the input string, but it didn't help.

Thanks for any assistance