[antlr-interest] NoViableAltException on a very simple grammar fragment?

[Vadim Tropashko]

Sorry for the today's noise, no more setup issues --
grammar question.

I have the following grammar fragment:

block_stmt:
         d_o_tDECLARE__decl_partd_o_t
          'BEGIN'
             seq_of_stmts
          d_o_tEXC__ehd_o_td_o_tehd_o_td_o_td_o_t
             'END' d_o_tsim_nd_o_t ';'
;

d_o_tDECLARE__decl_partd_o_t:  
|
  'DECLARE'
  decl_part  
;

which I'm expecting to have no difficulties to
recognize

begin
NULL;
end;

And the debugging trace indicates that there is some
problem:

0	Commence				
1	Enter rule block_stmt				
2	Location (1409,1)				
3	Enter alt 1				
4	Location (1410,3)				
5	Enter rule ph1psh_				
6	Location (436,1)				
7	Enter alt 1				
8	Location (438,1)				
9	Exit rule ph1psh_				
10	Location (1411,10)				
11	Enter rule d_o_tDECLARE__decl_partd_o_t				
12	Location (1418,1)				
13	Enter decision 114		114		
14	LT 1 (begin)		114		
15	LT 1 (begin)		114		
16	LT 1 (begin)		114		
17	Recognition exception
NoViableAltException(0!=[null])	



 
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