I'm trying to implement error recovery in this version of the project (make
followed by ./parse e1.input
to test).
Given (1
in e1.input
, I would like the parser to act as if it parsed )
and build an AST Paren (Int 1)
. Thus, I tried
let (startp, endp) = positions in
let _ = feed (T T_RPAREN) startp () endp env in
However, it returned an error Invalid_argument("feed: outgoing transition does not exist")
hahahaha depth of env 2
hahahaha current_state_number 2
hahahaha startp 1:1
hahahaha endp 1:2
element number of state 2
element startp 1:1
element endp 1:2
element incoming_symbol an integer
element v toComplete
element item: an expression -> an integer.
element number of state 1
element startp 1:0
element endp 1:1
element incoming_symbol (
element v toComplete
element item: an expression -> ( .an expression )
Line 1, characters 2-2: Error (parsing)
Error while analyzing an expression.
Fatal error: exception Invalid_argument("feed: outgoing transition does not exist")
Does anyone know why this error was raised?
CodePudding user response:
Before feeding )
, we should first reduce, the following code works:
let env_new = force_reduction (find_production 1) env in
let env_new_new = feed (T T_RPAREN) startp () endp env_new in
(lex, input_needed env_new_new)
For (1 2
for instance, we should reduce twice before feeding )
, the following code works:
let env_new = force_reduction (find_production 1) env in
let env_new_new = force_reduction (find_production 3) env_new in
let env_new_new_new = feed (T T_RPAREN) startp () endp env_new_new in
(lex, input_needed env_new_new_new)