[ragel-users] Best way to use error conditions

[Peter Gervais]

I need to parse an input set of characters with the following results :
If char = 'a' goto next state else call error
This logic would be used for every character in the string. The intent is to show exactly where the failure has occurred on the input string versus the expected string.
Ideally the error call could have a parameter such as an offset to indicate where within the string the match failed.
Any ideas would be greatly appreciated.

Pete Gervais



Sent from my iPhone

[Adrian Thurston]

Post by Peter Gervais
If char = 'a' goto next state else call error

You can do this by intersecting with 'm'.

action a { if ( !foo ) error(); }

Post by Peter Gervais
This logic would be used for every character in the string. The intent is to show exactly where the failure has occurred on the input string versus the expected string.
Ideally the error call could have a parameter such as an offset to indicate where within the string the match failed.
Any ideas would be greatly appreciated.

Also, you may want to use an error action.

-Adrian