sass-value-syntax.txt

This is the most-general grammar for property values in CSS.
It's taken from http://www.w3.org/TR/CSS2/syndata.html,
where the token definitions can be found.

value       : [ any | block | ATKEYWORD S* ]+;
at-rule     : ATKEYWORD S* any* [ block | ';' S* ];
block       : '{' S* [ any | block | ATKEYWORD S* | ';' S* ]* '}' S*;
any         : [ IDENT | NUMBER | PERCENTAGE | DIMENSION | STRING
              | DELIM | URI | HASH | UNICODE-RANGE | INCLUDES
              | DASHMATCH | ':' | FUNCTION S* any* ')' 
              | '(' S* any* ')' | '[' S* any* ']' ] S*;


This is the proposed Sass CSS-compatible value grammar.

value       : [ any | block | ATKEYWORD S* ]+;
at-rule     : ATKEYWORD S* any* [ block | ';' S* ];
block       : '{' S* [ any | block | ATKEYWORD S* | ';' S* ]* '}' S*;
any         : [ VARIABLE | IDENT | NUMBER | PERCENTAGE | DIMENSION | STRING
              | DELIM | URI | HASH | UNICODE-RANGE | INCLUDES
              | DASHMATCH | ':' | FUNCTION S* any* ')' 
              | '(' S* any* ')' | '[' S* any* ']' ] S*;