--- a/parser/calc/parser.y
+++ b/parser/calc/parser.y
@@ -21,66 +21,66 @@
 %%
 
 list:
-	/* empty */
-	| list stat '\n'
-	| list error '\n' { yyerrok; };
+    /* empty */
+    | list stat '\n'
+    | list error '\n' { yyerrok; };
 
 stat:
-	expr { (void) printf( "RESULT: %d\n", $1 ); }
-	| LETTER '=' expr { regs[$1] = $3; }
-	;
+    expr { (void) printf( "RESULT: %d\n", $1 ); }
+    | LETTER '=' expr { regs[$1] = $3; }
+    ;
 
 expr:
-	'(' expr ')'
-	{
-		$$ = $2;
-	}
-	| expr PLUS expr
-	{
-		$$ = $1 + $3;
-	}
-	| expr MINUS expr
-	{
-		$$ = $1 - $3;
-	}
-	| expr MUL expr
-	{
-		$$ = $1 * $3;
-	}
-	| expr DIV expr
-	{
-			$$ = $1 / $3;
-	}
-	| MINUS expr  %prec UMINUS
-	{
-		$$ = -$2;
-	}
-	| LETTER
-	{
-		$$ = regs[$1];
-	}
-	|  number
-	;
+    '(' expr ')'
+    {
+        $$ = $2;
+    }
+    | expr PLUS expr
+    {
+        $$ = $1 + $3;
+    }
+    | expr MINUS expr
+    {
+        $$ = $1 - $3;
+    }
+    | expr MUL expr
+    {
+        $$ = $1 * $3;
+    }
+    | expr DIV expr
+    {
+            $$ = $1 / $3;
+    }
+    | MINUS expr  %prec UMINUS
+    {
+        $$ = -$2;
+    }
+    | LETTER
+    {
+        $$ = regs[$1];
+    }
+    |  number
+    ;
 
 number:
-	DIGIT
-	{
-		$$ = $1; base = ($1==0) ? 8 : 10;
-	}
-	| number DIGIT
-	{
-		$$ = base * $1 + $2;
-	}
-	;
+    DIGIT
+    {
+        $$ = $1; base = ($1==0) ? 8 : 10;
+    }
+    | number DIGIT
+    {
+        $$ = base * $1 + $2;
+    }
+    ;
 %%
 
 int yyerror()
 {
-	printf("ERROR\n");
-	return 0;
+    printf("ERROR\n");
+    return 0;
 }
 
 int yywrap()
 {
-	return 1;
+    return 1;
 }