My grammar is Calc. it calc regular number and binary number. regular number has

Question

My grammar is Calc. it calc regular number and binary number.

regular number has its grammar and binary has its grammar

regular number has 0 and 1 also binary number has 0 and 1

so my problem is I want write regular number 0 or 1 like 1+1 or 0+1 but it is not work

grammar Expr;
// Program is a sequence of statements
prog :'<' bi+ '>'
| stat+
;
bi : '<' binary '>'
| NEWLINE   
;

binary : binary ('+' | '-' ) binary
| binary ('*' | '/' ) binary
| Binary_digit
;
stat : expr NEWLINE #print   
| CLEAR #clear
| ID '=' expr NEWLINE #assign
| INT '=' expr NEWLINE #assign
| NEWLINE #blank

;

expr : '-' expr #uminus // Unary minus
| expr op=('*' | '/' ) expr #MulDiv
| expr op=('+' | '-' ) expr #AddSub
| INT #int   
| ID #id
| '(' expr ')' #parens

;







MUL : '*';
DIV : '/';
ADD : '+';
SUB : '-';
EQ : '=' ;
GT : '>' ;
LT : '<' ;

// Keywords
CLEAR : 'clear';

Binary_digit : [01]+ ;
INT : ('0' .. '9')+ ('0' .. '1')+
;
DIGIT
: ('0' .. '1')+
;
ID : [a-zA-Z]+ ;
NEWLINE : [ ]+;
WS : [ ]+ -> skip;

rerror :

C:UsersFDesktopPL>grun Expr prog -gui
1+1
^Z
line 1:0 mismatched input '1' expecting {'(', '-', '<', 'clear', INT, ID, NEWLINE}

Explanation / Answer

I think the mistake you are doing is that you are giving the input as a string without any spaces, so just add spaces in between and program should work fine. So, effectively input should be 1 + 1. Please feel free to ask if you have any more doubts!!

Here is a much better grammar available, you can check it for your reference:

https://github.com/antlr/grammars-v4/tree/master/calculator

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