[antlr-interest] Lexer and Parser using CSharp3
Gian Maria
g_giacomello at yahoo.it
Sun Dec 19 04:43:30 PST 2010
program: start+;
start : (let | num);
let : LET;
num : NUM;
LET : ('a'..'z')+;
NUM : ('0'..'9')+;
WHITESPACE : ( '\t' | ' ' | '\r' | '\n' )+ { $channel = HIDDEN; };
1) Why inside Lexer and Parser all methods are declared Private (for example
the above "program" parser rule)? If I want to use one method of my Parser I
have to change it to public inside source code, is right to do this?
2) Is there a way to find if CommonTokenStream find some undefined chars in
the string?
In the above definition I want as input only lower case letters and number,
so if I write "123 aa 5 Bc" I want to detect the error at "B", How can I do
that?
The language I use is C# and the above code is a little example Just to test
the ANTLR functions to take me a Global understand of the potentiality.
Tank you for the support, I'm learning ANTLR but is not too easy at the
beginning.
Best regards Gian
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