Closed mingodad closed 2 years ago
yhirose
commented
2 years ago @mingodad, thanks for the report but there is very little information to investigate. Could you try to make the smallest possible grammar and source text, and also provide the profile result that is supposed to be? Then I'll start debugging. Thanks!
mingodad
commented
2 years ago I found one reason (maybe the only one) of the differences, it's at the end of file:
start <- _ (one / two / three)* EOF
one <- "one" _
two <- "two" _
three <- "three" _
_ <- [ \t\n\r]*
EOF <- !.Input:
one
two
three
When parsing the input three and succeeding we reach EOF cpp-peglib doesn't try again to parse (one / two / three) somehow it check the end of file before and stop.
cpp-peglib profile output:
duration: 0.0001s (100µs)
id total % success fail definition
12 9 3 Total counters
75.00 25.00 % success/fail
0 1 8.33 1 0 start
1 4 33.33 4 0 _
2 3 25.00 1 2 one
3 2 16.67 1 1 two
4 1 8.33 1 0 three
5 1 8.33 1 0 EOFchpeg (peg/leg) profile output:
Definition identifier calls:
DEF- id IDENT % ISUCC IFAIL name
DEF 0 1 6.67 1 0 start
DEF 1 4 26.67 1 3 one
DEF 2 3 20.00 1 2 two
DEF 3 2 13.33 1 1 three
DEF 4 4 26.67 4 0 _
DEF 5 1 6.67 1 0 EOF
DEF= -- 15 100.00 9 6 --With the modified example shown bellow and the same input as above/before cpp-peglib doesn't attempt the rule four but chpeg/peg/leg does.
start <- _ (one / two / three)* four? EOF
one <- "one" _
two <- "two" _
three <- "three" _
four <- "four" _
_ <- [ \t\n\r]*
EOF <- !.cpp-peglib profile output:
duration: 0s (0µs)
id total % success fail definition
12 9 3 Total counters
75.00 25.00 % success/fail
0 1 8.33 1 0 start
1 4 33.33 4 0 _
2 3 25.00 1 2 one
3 2 16.67 1 1 two
4 1 8.33 1 0 three
5 1 8.33 1 0 EOFchpeg (peg/leg) profile output:
Definition identifier calls:
DEF- id IDENT % ISUCC IFAIL name
DEF 0 1 6.25 1 0 start
DEF 1 4 25.00 1 3 one
DEF 2 3 18.75 1 2 two
DEF 3 2 12.50 1 1 three
DEF 4 1 6.25 0 1 four
DEF 5 4 25.00 4 0 _
DEF 6 1 6.25 1 0 EOF
DEF= -- 16 100.00 9 7 --And if we make the rule four not optional then cpp-peglib does complain with an error and register the rule four on the profile output but doesn't register an extra failure on the sequence (one / two / three).
start <- _ (one / two / three)* four EOF
one <- "one" _
two <- "two" _
three <- "three" _
four <- "four" _
_ <- [ \t\n\r]*
EOF <- !.profile output:
duration: 0.0001s (100µs)
id total % success fail definition
12 7 5 Total counters
58.33 41.67 % success/fail
0 1 8.33 0 1 start
1 4 33.33 4 0 _
2 3 25.00 1 2 one
3 2 16.67 1 1 two
4 1 8.33 1 0 three
5 1 8.33 0 1 fourError message:
5:1 syntax error, expecting 'four'.@mingodad, thanks for the report!
Attached is a zip file with the grammars and input data used to compare the output of profile without packrat, there is a spreadsheet with the output of each (peg/leg, chpeg and cpp-peglib) where peg/leg and chpeg have the same profile numbers but peglib has some small deviation in several of then. I do not know yet what this difference means.
kotlin-diff.zip